This is a preview of a developing guide for information only. It is not intended to be used until the completed v1.0.0 guide is released (around the end of March 2023)
If you are interested in developing a BaRS compliant solution right now, please use the contact form here and the team will be in touch
- BARS Bundle Message
- BARS MessageHeader - Booking-Request
- BARS MessageHeader - ServiceRequest-Request
- BARS MessageHeader - ServiceRequest-Response
- BARS ServiceRequest-Request Referral
- BARS ServiceRequest-Request Validation
- BARS MessageDefinition Booking-Request
- BARS MessageDefinition ServiceRequest-RequestReferral
- BARS MessageDefinition ServiceRequest-ResponseReferral
- BARS MessageDefinition ServiceRequest-RequestValidation
- BARS MessageDefinition ServiceRequest-ResponseValidationInterim
- BARS MessageDefinition ServiceRequest-ResponseValidationFull
All Profiles
BARS Bundle Message
Defines the constraints and extensions on the UKCore-Bundle FHIR Profile
Based on: UKCore.Release1@1.0.1/package/UKCore-Bundle
Differential View
| Bundle | I | Bundle | There are no (further) constraints on this elementElement Id Bundle Contains a collection of resourcesDefinition A container for a collection of resources. 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id Bundle.identifier Persistent identifier for the bundleDefinition A persistent identifier for the bundle that won't change as a bundle is copied from server to server. Persistent identity generally only matters for batches of type Document, Message, and Collection. It would not normally be populated for search and history results and servers ignore Bundle.identifier when processing batches and transactions. For Documents the .identifier SHALL be populated such that the .identifier is globally unique. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id Bundle.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id Bundle.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id Bundle.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| type | Σ | 1..1 | codeBindingFixed Value | Element Id Bundle.type document | message | transaction | transaction-response | batch | batch-response | history | searchset | collectionDefinition Indicates the purpose of this bundle - how it is intended to be used. It's possible to use a bundle for other purposes (e.g. a document can be accepted as a transaction). This is primarily defined so that there can be specific rules for some of the bundle types. Indicates the purpose of a bundle - how it is intended to be used.BundleType (required)Constraints 
 message 
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| timestamp | Σ | 1..1 | instant | There are no (further) constraints on this elementElement Id Bundle.timestamp When the bundle was assembledDefinition The date/time that the bundle was assembled - i.e. when the resources were placed in the bundle. For many bundles, the timestamp is equal to .meta.lastUpdated, because they are not stored (e.g. search results). When a bundle is placed in a persistent store, .meta.lastUpdated will be usually be changed by the server. When the bundle is a message, a middleware agent altering the message (even if not stored) SHOULD update .meta.lastUpdated. .timestamp is used to track the original time of the Bundle, and SHOULD be populated. Usage: 
 The timestamp value should be greater than the lastUpdated and other timestamps in the resources in the bundle, and it should be equal or earlier than the .meta.lastUpdated on the Bundle itself. 
 
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| total | Σ I | 0..1 | unsignedInt | There are no (further) constraints on this elementElement Id Bundle.total If search, the total number of matchesDefinition If a set of search matches, this is the total number of entries of type 'match' across all pages in the search. It does not include search.mode = 'include' or 'outcome' entries and it does not provide a count of the number of entries in the Bundle. Only used if the bundle is a search result set. The total does not include resources such as OperationOutcome and included resources, only the total number of matching resources. 
 
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| link | Σ | 0..* | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.link Links related to this BundleDefinition A series of links that provide context to this bundle. Both Bundle.link and Bundle.entry.link are defined to support providing additional context when Bundles are used (e.g. HATEOAS). Bundle.entry.link corresponds to links found in the HTTP header if the resource in the entry was read directly. This specification defines some specific uses of Bundle.link for searching and paging, but no specific uses for Bundle.entry.link, and no defined function in a transaction - the meaning is implementation specific. 
 
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| relation | Σ | 1..1 | string | There are no (further) constraints on this elementElement Id Bundle.link.relation See http://www.iana.org/assignments/link-relations/link-relations.xhtml#link-relations-1Definition A name which details the functional use for this link - see http://www.iana.org/assignments/link-relations/link-relations.xhtml#link-relations-1. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| url | Σ | 1..1 | uri | There are no (further) constraints on this elementElement Id Bundle.link.url Reference details for the linkDefinition The reference details for the link. see http://en.wikipedia.org/wiki/Uniform_resource_identifier 
 
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| entry | Σ I | 0..* | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.entry Entry in the bundle - will have a resource or informationDefinition An entry in a bundle resource - will either contain a resource or information about a resource (transactions and history only). 
 
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| link | Σ | 0..* | see (link) | There are no (further) constraints on this elementElement Id Bundle.entry.link Links related to this entryDefinition A series of links that provide context to this entry. | 
| fullUrl | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.entry.fullUrl URI for resource (Absolute URL server address or URI for UUID/OID)Definition The Absolute URL for the resource. The fullUrl SHALL NOT disagree with the id in the resource - i.e. if the fullUrl is not a urn:uuid, the URL shall be version-independent URL consistent with the Resource.id. The fullUrl is a version independent reference to the resource. The fullUrl element SHALL have a value except that: 
 fullUrl might not be unique in the context of a resource. Note that since FHIR resources do not need to be served through the FHIR API, the fullURL might be a URN or an absolute URL that does not end with the logical id of the resource (Resource.id). However, but if the fullUrl does look like a RESTful server URL (e.g. meets the regex, then the 'id' portion of the fullUrl SHALL end with the Resource.id. Note that the fullUrl is not the same as the canonical URL - it's an absolute url for an endpoint serving the resource (these will happen to have the same value on the canonical server for the resource with the canonical URL). 
 
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| resource | Σ | 0..1 | Resource | There are no (further) constraints on this elementElement Id Bundle.entry.resource A resource in the bundleDefinition The Resource for the entry. The purpose/meaning of the resource is determined by the Bundle.type. 
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| search | Σ I | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.entry.search Search related informationDefinition Information about the search process that lead to the creation of this entry. 
 
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| mode | Σ | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.entry.search.mode match | include | outcome - why this is in the result setDefinition Why this entry is in the result set - whether it's included as a match or because of an _include requirement, or to convey information or warning information about the search process. There is only one mode. In some corner cases, a resource may be included because it is both a match and an include. In these circumstances, 'match' takes precedence. Why an entry is in the result set - whether it's included as a match or because of an _include requirement, or to convey information or warning information about the search process.SearchEntryMode (required)Constraints 
 
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| score | Σ | 0..1 | decimal | There are no (further) constraints on this elementElement Id Bundle.entry.search.score Search ranking (between 0 and 1)Definition When searching, the server's search ranking score for the entry. Servers are not required to return a ranking score. 1 is most relevant, and 0 is least relevant. Often, search results are sorted by score, but the client may specify a different sort order. See Patient Match for the EMPI search which relates to this element. 
 
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| request | Σ I | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.entry.request Additional execution information (transaction/batch/history)Definition Additional information about how this entry should be processed as part of a transaction or batch. For history, it shows how the entry was processed to create the version contained in the entry. 
 
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| method | Σ | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.entry.request.method GET | HEAD | POST | PUT | DELETE | PATCHDefinition In a transaction or batch, this is the HTTP action to be executed for this entry. In a history bundle, this indicates the HTTP action that occurred. Note that FHIR strings SHALL NOT exceed 1MB in size HTTP verbs (in the HTTP command line). See [HTTP rfc](https://tools.ietf.org/html/rfc7231) for details.HTTPVerb (required)Constraints 
 
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| url | Σ | 1..1 | uri | There are no (further) constraints on this elementElement Id Bundle.entry.request.url URL for HTTP equivalent of this entryDefinition The URL for this entry, relative to the root (the address to which the request is posted). E.g. for a Patient Create, the method would be "POST" and the URL would be "Patient". For a Patient Update, the method would be PUT and the URL would be "Patient/[id]". 
 
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| ifNoneMatch | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.request.ifNoneMatch For managing cache currencyDefinition If the ETag values match, return a 304 Not Modified status. See the API documentation for "Conditional Read". Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| ifModifiedSince | Σ | 0..1 | instant | There are no (further) constraints on this elementElement Id Bundle.entry.request.ifModifiedSince For managing cache currencyDefinition Only perform the operation if the last updated date matches. See the API documentation for "Conditional Read". Note: This is intended for where precisely observed times are required, typically system logs etc., and not human-reported times - for them, see date and dateTime (which can be as precise as instant, but is not required to be) below. Time zone is always required 
 
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| ifMatch | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.request.ifMatch For managing update contentionDefinition Only perform the operation if the Etag value matches. For more information, see the API section "Managing Resource Contention". Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| ifNoneExist | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.request.ifNoneExist For conditional createsDefinition Instruct the server not to perform the create if a specified resource already exists. For further information, see the API documentation for "Conditional Create". This is just the query portion of the URL - what follows the "?" (not including the "?"). Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| response | Σ I | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.entry.response Results of execution (transaction/batch/history)Definition Indicates the results of processing the corresponding 'request' entry in the batch or transaction being responded to or what the results of an operation where when returning history. 
 
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| status | Σ | 1..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.response.status Status response code (text optional)Definition The status code returned by processing this entry. The status SHALL start with a 3 digit HTTP code (e.g. 404) and may contain the standard HTTP description associated with the status code. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| location | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.entry.response.location The location (if the operation returns a location)Definition The location header created by processing this operation, populated if the operation returns a location. see http://en.wikipedia.org/wiki/Uniform_resource_identifier 
 
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| etag | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.response.etag The Etag for the resource (if relevant)Definition The Etag for the resource, if the operation for the entry produced a versioned resource (see Resource Metadata and Versioning and Managing Resource Contention). Etags match the Resource.meta.versionId. The ETag has to match the version id in the header if a resource is included. 
 
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| lastModified | Σ | 0..1 | instant | There are no (further) constraints on this elementElement Id Bundle.entry.response.lastModified Server's date time modifiedDefinition The date/time that the resource was modified on the server. This has to match the same time in the meta header (meta.lastUpdated) if a resource is included. 
 
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| outcome | Σ | 0..1 | Resource | There are no (further) constraints on this elementElement Id Bundle.entry.response.outcome OperationOutcome with hints and warnings (for batch/transaction)Definition An OperationOutcome containing hints and warnings produced as part of processing this entry in a batch or transaction. For a POST/PUT operation, this is the equivalent outcome that would be returned for prefer = operationoutcome - except that the resource is always returned whether or not the outcome is returned. This outcome is not used for error responses in batch/transaction, only for hints and warnings. In a batch operation, the error will be in Bundle.entry.response, and for transaction, there will be a single OperationOutcome instead of a bundle in the case of an error. 
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| signature | Σ | 0..1 | Signature | There are no (further) constraints on this elementElement Id Bundle.signature Digital SignatureDefinition Digital Signature - base64 encoded. XML-DSig or a JWT. A Signature holds an electronic representation of a signature and its supporting context in a FHIR accessible form. The signature may either be a cryptographic type (XML DigSig or a JWS), which is able to provide non-repudiation proof, or it may be a graphical image that represents a signature or a signature process. This element allows capturing signatures on documents, messages, transactions or even search responses, to support content-authentication, non-repudiation or other business cases. This is primarily relevant where the bundle may travel through multiple hops or via other mechanisms where HTTPS non-repudiation is insufficient. The signature could be created by the "author" of the bundle or by the originating device. Requirements around inclusion of a signature, verification of signatures and treatment of signed/non-signed bundles is implementation-environment specific. 
 
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| type | Σ | 1..* | CodingBinding | There are no (further) constraints on this elementElement Id Bundle.signature.type Indication of the reason the entity signed the object(s)Definition An indication of the reason that the entity signed this document. This may be explicitly included as part of the signature information and can be used when determining accountability for various actions concerning the document. Examples include attesting to: authorship, correct transcription, and witness of specific event. Also known as a "Commitment Type Indication". An indication of the reason that an entity signed the object.SignatureTypeCodes (preferred)Constraints 
 
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| when | Σ | 1..1 | instant | There are no (further) constraints on this elementElement Id Bundle.signature.when When the signature was createdDefinition When the digital signature was signed. This should agree with the information in the signature. 
 
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| who | Σ I | 1..1 | Reference(Device | UK Core PractitionerRole | UK Core Organization | UK Core Practitioner | UK Core RelatedPerson | UK Core Patient) | There are no (further) constraints on this elementElement Id Bundle.signature.who Who signedDefinition A reference to an application-usable description of the identity that signed (e.g. the signature used their private key). This should agree with the information in the signature. Reference(Device | UK Core PractitionerRole | UK Core Organization | UK Core Practitioner | UK Core RelatedPerson | UK Core Patient)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.who.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id Bundle.signature.who.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.who.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| onBehalfOf | Σ I | 0..1 | Reference(Device | UK Core PractitionerRole | UK Core Organization | UK Core Practitioner | UK Core RelatedPerson | UK Core Patient) | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf The party representedDefinition A reference to an application-usable description of the identity that is represented by the signature. used when the signature is on behalf of a non-signer. The party that can't sign. For example a child. Reference(Device | UK Core PractitionerRole | UK Core Organization | UK Core Practitioner | UK Core RelatedPerson | UK Core Patient)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| targetFormat | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.signature.targetFormat The technical format of the signed resourcesDefinition A mime type that indicates the technical format of the target resources signed by the signature. "xml", "json" and "ttl" are allowed, which describe the simple encodings described in the specification (and imply appropriate bundle support). Otherwise, mime types are legal here. The mime type of an attachment. Any valid mime type is allowed.Mime Types (required)Constraints 
 
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| sigFormat | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.signature.sigFormat The technical format of the signatureDefinition A mime type that indicates the technical format of the signature. Important mime types are application/signature+xml for X ML DigSig, application/jose for JWS, and image/* for a graphical image of a signature, etc. Note that FHIR strings SHALL NOT exceed 1MB in size The mime type of an attachment. Any valid mime type is allowed.Mime Types (required)Constraints 
 
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| data | 0..1 | base64Binary | There are no (further) constraints on this elementElement Id Bundle.signature.data The actual signature content (XML DigSig. JWS, picture, etc.)Definition The base64 encoding of the Signature content. When signature is not recorded electronically this element would be empty. Where the signature type is an XML DigSig, the signed content is a FHIR Resource(s), the signature is of the XML form of the Resource(s) using XML-Signature (XMLDIG) "Detached Signature" form. 
 
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Hybrid View
| Bundle | I | Bundle | There are no (further) constraints on this elementElement Id Bundle Contains a collection of resourcesDefinition A container for a collection of resources. 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id Bundle.identifier Persistent identifier for the bundleDefinition A persistent identifier for the bundle that won't change as a bundle is copied from server to server. Persistent identity generally only matters for batches of type Document, Message, and Collection. It would not normally be populated for search and history results and servers ignore Bundle.identifier when processing batches and transactions. For Documents the .identifier SHALL be populated such that the .identifier is globally unique. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id Bundle.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id Bundle.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id Bundle.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| type | Σ | 1..1 | codeBindingFixed Value | Element Id Bundle.type document | message | transaction | transaction-response | batch | batch-response | history | searchset | collectionDefinition Indicates the purpose of this bundle - how it is intended to be used. It's possible to use a bundle for other purposes (e.g. a document can be accepted as a transaction). This is primarily defined so that there can be specific rules for some of the bundle types. Indicates the purpose of a bundle - how it is intended to be used.BundleType (required)Constraints 
 message 
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| timestamp | Σ | 1..1 | instant | There are no (further) constraints on this elementElement Id Bundle.timestamp When the bundle was assembledDefinition The date/time that the bundle was assembled - i.e. when the resources were placed in the bundle. For many bundles, the timestamp is equal to .meta.lastUpdated, because they are not stored (e.g. search results). When a bundle is placed in a persistent store, .meta.lastUpdated will be usually be changed by the server. When the bundle is a message, a middleware agent altering the message (even if not stored) SHOULD update .meta.lastUpdated. .timestamp is used to track the original time of the Bundle, and SHOULD be populated. Usage: 
 The timestamp value should be greater than the lastUpdated and other timestamps in the resources in the bundle, and it should be equal or earlier than the .meta.lastUpdated on the Bundle itself. 
 
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| total | Σ I | 0..1 | unsignedInt | There are no (further) constraints on this elementElement Id Bundle.total If search, the total number of matchesDefinition If a set of search matches, this is the total number of entries of type 'match' across all pages in the search. It does not include search.mode = 'include' or 'outcome' entries and it does not provide a count of the number of entries in the Bundle. Only used if the bundle is a search result set. The total does not include resources such as OperationOutcome and included resources, only the total number of matching resources. 
 
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| link | Σ | 0..* | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.link Links related to this BundleDefinition A series of links that provide context to this bundle. Both Bundle.link and Bundle.entry.link are defined to support providing additional context when Bundles are used (e.g. HATEOAS). Bundle.entry.link corresponds to links found in the HTTP header if the resource in the entry was read directly. This specification defines some specific uses of Bundle.link for searching and paging, but no specific uses for Bundle.entry.link, and no defined function in a transaction - the meaning is implementation specific. 
 
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| relation | Σ | 1..1 | string | There are no (further) constraints on this elementElement Id Bundle.link.relation See http://www.iana.org/assignments/link-relations/link-relations.xhtml#link-relations-1Definition A name which details the functional use for this link - see http://www.iana.org/assignments/link-relations/link-relations.xhtml#link-relations-1. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| url | Σ | 1..1 | uri | There are no (further) constraints on this elementElement Id Bundle.link.url Reference details for the linkDefinition The reference details for the link. see http://en.wikipedia.org/wiki/Uniform_resource_identifier 
 
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| entry | Σ I | 0..* | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.entry Entry in the bundle - will have a resource or informationDefinition An entry in a bundle resource - will either contain a resource or information about a resource (transactions and history only). 
 
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| link | Σ | 0..* | see (link) | There are no (further) constraints on this elementElement Id Bundle.entry.link Links related to this entryDefinition A series of links that provide context to this entry. | 
| fullUrl | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.entry.fullUrl URI for resource (Absolute URL server address or URI for UUID/OID)Definition The Absolute URL for the resource. The fullUrl SHALL NOT disagree with the id in the resource - i.e. if the fullUrl is not a urn:uuid, the URL shall be version-independent URL consistent with the Resource.id. The fullUrl is a version independent reference to the resource. The fullUrl element SHALL have a value except that: 
 fullUrl might not be unique in the context of a resource. Note that since FHIR resources do not need to be served through the FHIR API, the fullURL might be a URN or an absolute URL that does not end with the logical id of the resource (Resource.id). However, but if the fullUrl does look like a RESTful server URL (e.g. meets the regex, then the 'id' portion of the fullUrl SHALL end with the Resource.id. Note that the fullUrl is not the same as the canonical URL - it's an absolute url for an endpoint serving the resource (these will happen to have the same value on the canonical server for the resource with the canonical URL). 
 
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| resource | Σ | 0..1 | Resource | There are no (further) constraints on this elementElement Id Bundle.entry.resource A resource in the bundleDefinition The Resource for the entry. The purpose/meaning of the resource is determined by the Bundle.type. 
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| search | Σ I | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.entry.search Search related informationDefinition Information about the search process that lead to the creation of this entry. 
 
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| mode | Σ | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.entry.search.mode match | include | outcome - why this is in the result setDefinition Why this entry is in the result set - whether it's included as a match or because of an _include requirement, or to convey information or warning information about the search process. There is only one mode. In some corner cases, a resource may be included because it is both a match and an include. In these circumstances, 'match' takes precedence. Why an entry is in the result set - whether it's included as a match or because of an _include requirement, or to convey information or warning information about the search process.SearchEntryMode (required)Constraints 
 
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| score | Σ | 0..1 | decimal | There are no (further) constraints on this elementElement Id Bundle.entry.search.score Search ranking (between 0 and 1)Definition When searching, the server's search ranking score for the entry. Servers are not required to return a ranking score. 1 is most relevant, and 0 is least relevant. Often, search results are sorted by score, but the client may specify a different sort order. See Patient Match for the EMPI search which relates to this element. 
 
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| request | Σ I | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.entry.request Additional execution information (transaction/batch/history)Definition Additional information about how this entry should be processed as part of a transaction or batch. For history, it shows how the entry was processed to create the version contained in the entry. 
 
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| method | Σ | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.entry.request.method GET | HEAD | POST | PUT | DELETE | PATCHDefinition In a transaction or batch, this is the HTTP action to be executed for this entry. In a history bundle, this indicates the HTTP action that occurred. Note that FHIR strings SHALL NOT exceed 1MB in size HTTP verbs (in the HTTP command line). See [HTTP rfc](https://tools.ietf.org/html/rfc7231) for details.HTTPVerb (required)Constraints 
 
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| url | Σ | 1..1 | uri | There are no (further) constraints on this elementElement Id Bundle.entry.request.url URL for HTTP equivalent of this entryDefinition The URL for this entry, relative to the root (the address to which the request is posted). E.g. for a Patient Create, the method would be "POST" and the URL would be "Patient". For a Patient Update, the method would be PUT and the URL would be "Patient/[id]". 
 
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| ifNoneMatch | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.request.ifNoneMatch For managing cache currencyDefinition If the ETag values match, return a 304 Not Modified status. See the API documentation for "Conditional Read". Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| ifModifiedSince | Σ | 0..1 | instant | There are no (further) constraints on this elementElement Id Bundle.entry.request.ifModifiedSince For managing cache currencyDefinition Only perform the operation if the last updated date matches. See the API documentation for "Conditional Read". Note: This is intended for where precisely observed times are required, typically system logs etc., and not human-reported times - for them, see date and dateTime (which can be as precise as instant, but is not required to be) below. Time zone is always required 
 
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| ifMatch | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.request.ifMatch For managing update contentionDefinition Only perform the operation if the Etag value matches. For more information, see the API section "Managing Resource Contention". Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| ifNoneExist | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.request.ifNoneExist For conditional createsDefinition Instruct the server not to perform the create if a specified resource already exists. For further information, see the API documentation for "Conditional Create". This is just the query portion of the URL - what follows the "?" (not including the "?"). Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| response | Σ I | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.entry.response Results of execution (transaction/batch/history)Definition Indicates the results of processing the corresponding 'request' entry in the batch or transaction being responded to or what the results of an operation where when returning history. 
 
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| status | Σ | 1..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.response.status Status response code (text optional)Definition The status code returned by processing this entry. The status SHALL start with a 3 digit HTTP code (e.g. 404) and may contain the standard HTTP description associated with the status code. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| location | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.entry.response.location The location (if the operation returns a location)Definition The location header created by processing this operation, populated if the operation returns a location. see http://en.wikipedia.org/wiki/Uniform_resource_identifier 
 
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| etag | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.response.etag The Etag for the resource (if relevant)Definition The Etag for the resource, if the operation for the entry produced a versioned resource (see Resource Metadata and Versioning and Managing Resource Contention). Etags match the Resource.meta.versionId. The ETag has to match the version id in the header if a resource is included. 
 
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| lastModified | Σ | 0..1 | instant | There are no (further) constraints on this elementElement Id Bundle.entry.response.lastModified Server's date time modifiedDefinition The date/time that the resource was modified on the server. This has to match the same time in the meta header (meta.lastUpdated) if a resource is included. 
 
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| outcome | Σ | 0..1 | Resource | There are no (further) constraints on this elementElement Id Bundle.entry.response.outcome OperationOutcome with hints and warnings (for batch/transaction)Definition An OperationOutcome containing hints and warnings produced as part of processing this entry in a batch or transaction. For a POST/PUT operation, this is the equivalent outcome that would be returned for prefer = operationoutcome - except that the resource is always returned whether or not the outcome is returned. This outcome is not used for error responses in batch/transaction, only for hints and warnings. In a batch operation, the error will be in Bundle.entry.response, and for transaction, there will be a single OperationOutcome instead of a bundle in the case of an error. 
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| signature | Σ | 0..1 | Signature | There are no (further) constraints on this elementElement Id Bundle.signature Digital SignatureDefinition Digital Signature - base64 encoded. XML-DSig or a JWT. A Signature holds an electronic representation of a signature and its supporting context in a FHIR accessible form. The signature may either be a cryptographic type (XML DigSig or a JWS), which is able to provide non-repudiation proof, or it may be a graphical image that represents a signature or a signature process. This element allows capturing signatures on documents, messages, transactions or even search responses, to support content-authentication, non-repudiation or other business cases. This is primarily relevant where the bundle may travel through multiple hops or via other mechanisms where HTTPS non-repudiation is insufficient. The signature could be created by the "author" of the bundle or by the originating device. Requirements around inclusion of a signature, verification of signatures and treatment of signed/non-signed bundles is implementation-environment specific. 
 
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| type | Σ | 1..* | CodingBinding | There are no (further) constraints on this elementElement Id Bundle.signature.type Indication of the reason the entity signed the object(s)Definition An indication of the reason that the entity signed this document. This may be explicitly included as part of the signature information and can be used when determining accountability for various actions concerning the document. Examples include attesting to: authorship, correct transcription, and witness of specific event. Also known as a "Commitment Type Indication". An indication of the reason that an entity signed the object.SignatureTypeCodes (preferred)Constraints 
 
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| when | Σ | 1..1 | instant | There are no (further) constraints on this elementElement Id Bundle.signature.when When the signature was createdDefinition When the digital signature was signed. This should agree with the information in the signature. 
 
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| who | Σ I | 1..1 | Reference(Device | UK Core PractitionerRole | UK Core Organization | UK Core Practitioner | UK Core RelatedPerson | UK Core Patient) | There are no (further) constraints on this elementElement Id Bundle.signature.who Who signedDefinition A reference to an application-usable description of the identity that signed (e.g. the signature used their private key). This should agree with the information in the signature. Reference(Device | UK Core PractitionerRole | UK Core Organization | UK Core Practitioner | UK Core RelatedPerson | UK Core Patient)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.who.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id Bundle.signature.who.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.who.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| onBehalfOf | Σ I | 0..1 | Reference(Device | UK Core PractitionerRole | UK Core Organization | UK Core Practitioner | UK Core RelatedPerson | UK Core Patient) | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf The party representedDefinition A reference to an application-usable description of the identity that is represented by the signature. used when the signature is on behalf of a non-signer. The party that can't sign. For example a child. Reference(Device | UK Core PractitionerRole | UK Core Organization | UK Core Practitioner | UK Core RelatedPerson | UK Core Patient)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| targetFormat | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.signature.targetFormat The technical format of the signed resourcesDefinition A mime type that indicates the technical format of the target resources signed by the signature. "xml", "json" and "ttl" are allowed, which describe the simple encodings described in the specification (and imply appropriate bundle support). Otherwise, mime types are legal here. The mime type of an attachment. Any valid mime type is allowed.Mime Types (required)Constraints 
 
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| sigFormat | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.signature.sigFormat The technical format of the signatureDefinition A mime type that indicates the technical format of the signature. Important mime types are application/signature+xml for X ML DigSig, application/jose for JWS, and image/* for a graphical image of a signature, etc. Note that FHIR strings SHALL NOT exceed 1MB in size The mime type of an attachment. Any valid mime type is allowed.Mime Types (required)Constraints 
 
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| data | 0..1 | base64Binary | There are no (further) constraints on this elementElement Id Bundle.signature.data The actual signature content (XML DigSig. JWS, picture, etc.)Definition The base64 encoding of the Signature content. When signature is not recorded electronically this element would be empty. Where the signature type is an XML DigSig, the signed content is a FHIR Resource(s), the signature is of the XML form of the Resource(s) using XML-Signature (XMLDIG) "Detached Signature" form. 
 
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Snapshot View
| Bundle | I | Bundle | There are no (further) constraints on this elementElement Id Bundle Contains a collection of resourcesDefinition A container for a collection of resources. 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id Bundle.identifier Persistent identifier for the bundleDefinition A persistent identifier for the bundle that won't change as a bundle is copied from server to server. Persistent identity generally only matters for batches of type Document, Message, and Collection. It would not normally be populated for search and history results and servers ignore Bundle.identifier when processing batches and transactions. For Documents the .identifier SHALL be populated such that the .identifier is globally unique. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id Bundle.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id Bundle.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id Bundle.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| type | Σ | 1..1 | codeBindingFixed Value | Element Id Bundle.type document | message | transaction | transaction-response | batch | batch-response | history | searchset | collectionDefinition Indicates the purpose of this bundle - how it is intended to be used. It's possible to use a bundle for other purposes (e.g. a document can be accepted as a transaction). This is primarily defined so that there can be specific rules for some of the bundle types. Indicates the purpose of a bundle - how it is intended to be used.BundleType (required)Constraints 
 message 
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| timestamp | Σ | 1..1 | instant | There are no (further) constraints on this elementElement Id Bundle.timestamp When the bundle was assembledDefinition The date/time that the bundle was assembled - i.e. when the resources were placed in the bundle. For many bundles, the timestamp is equal to .meta.lastUpdated, because they are not stored (e.g. search results). When a bundle is placed in a persistent store, .meta.lastUpdated will be usually be changed by the server. When the bundle is a message, a middleware agent altering the message (even if not stored) SHOULD update .meta.lastUpdated. .timestamp is used to track the original time of the Bundle, and SHOULD be populated. Usage: 
 The timestamp value should be greater than the lastUpdated and other timestamps in the resources in the bundle, and it should be equal or earlier than the .meta.lastUpdated on the Bundle itself. 
 
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| total | Σ I | 0..1 | unsignedInt | There are no (further) constraints on this elementElement Id Bundle.total If search, the total number of matchesDefinition If a set of search matches, this is the total number of entries of type 'match' across all pages in the search. It does not include search.mode = 'include' or 'outcome' entries and it does not provide a count of the number of entries in the Bundle. Only used if the bundle is a search result set. The total does not include resources such as OperationOutcome and included resources, only the total number of matching resources. 
 
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| link | Σ | 0..* | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.link Links related to this BundleDefinition A series of links that provide context to this bundle. Both Bundle.link and Bundle.entry.link are defined to support providing additional context when Bundles are used (e.g. HATEOAS). Bundle.entry.link corresponds to links found in the HTTP header if the resource in the entry was read directly. This specification defines some specific uses of Bundle.link for searching and paging, but no specific uses for Bundle.entry.link, and no defined function in a transaction - the meaning is implementation specific. 
 
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| relation | Σ | 1..1 | string | There are no (further) constraints on this elementElement Id Bundle.link.relation See http://www.iana.org/assignments/link-relations/link-relations.xhtml#link-relations-1Definition A name which details the functional use for this link - see http://www.iana.org/assignments/link-relations/link-relations.xhtml#link-relations-1. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| url | Σ | 1..1 | uri | There are no (further) constraints on this elementElement Id Bundle.link.url Reference details for the linkDefinition The reference details for the link. see http://en.wikipedia.org/wiki/Uniform_resource_identifier 
 
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| entry | Σ I | 0..* | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.entry Entry in the bundle - will have a resource or informationDefinition An entry in a bundle resource - will either contain a resource or information about a resource (transactions and history only). 
 
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| link | Σ | 0..* | see (link) | There are no (further) constraints on this elementElement Id Bundle.entry.link Links related to this entryDefinition A series of links that provide context to this entry. | 
| fullUrl | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.entry.fullUrl URI for resource (Absolute URL server address or URI for UUID/OID)Definition The Absolute URL for the resource. The fullUrl SHALL NOT disagree with the id in the resource - i.e. if the fullUrl is not a urn:uuid, the URL shall be version-independent URL consistent with the Resource.id. The fullUrl is a version independent reference to the resource. The fullUrl element SHALL have a value except that: 
 fullUrl might not be unique in the context of a resource. Note that since FHIR resources do not need to be served through the FHIR API, the fullURL might be a URN or an absolute URL that does not end with the logical id of the resource (Resource.id). However, but if the fullUrl does look like a RESTful server URL (e.g. meets the regex, then the 'id' portion of the fullUrl SHALL end with the Resource.id. Note that the fullUrl is not the same as the canonical URL - it's an absolute url for an endpoint serving the resource (these will happen to have the same value on the canonical server for the resource with the canonical URL). 
 
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| resource | Σ | 0..1 | Resource | There are no (further) constraints on this elementElement Id Bundle.entry.resource A resource in the bundleDefinition The Resource for the entry. The purpose/meaning of the resource is determined by the Bundle.type. 
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| search | Σ I | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.entry.search Search related informationDefinition Information about the search process that lead to the creation of this entry. 
 
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| mode | Σ | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.entry.search.mode match | include | outcome - why this is in the result setDefinition Why this entry is in the result set - whether it's included as a match or because of an _include requirement, or to convey information or warning information about the search process. There is only one mode. In some corner cases, a resource may be included because it is both a match and an include. In these circumstances, 'match' takes precedence. Why an entry is in the result set - whether it's included as a match or because of an _include requirement, or to convey information or warning information about the search process.SearchEntryMode (required)Constraints 
 
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| score | Σ | 0..1 | decimal | There are no (further) constraints on this elementElement Id Bundle.entry.search.score Search ranking (between 0 and 1)Definition When searching, the server's search ranking score for the entry. Servers are not required to return a ranking score. 1 is most relevant, and 0 is least relevant. Often, search results are sorted by score, but the client may specify a different sort order. See Patient Match for the EMPI search which relates to this element. 
 
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| request | Σ I | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.entry.request Additional execution information (transaction/batch/history)Definition Additional information about how this entry should be processed as part of a transaction or batch. For history, it shows how the entry was processed to create the version contained in the entry. 
 
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| method | Σ | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.entry.request.method GET | HEAD | POST | PUT | DELETE | PATCHDefinition In a transaction or batch, this is the HTTP action to be executed for this entry. In a history bundle, this indicates the HTTP action that occurred. Note that FHIR strings SHALL NOT exceed 1MB in size HTTP verbs (in the HTTP command line). See [HTTP rfc](https://tools.ietf.org/html/rfc7231) for details.HTTPVerb (required)Constraints 
 
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| url | Σ | 1..1 | uri | There are no (further) constraints on this elementElement Id Bundle.entry.request.url URL for HTTP equivalent of this entryDefinition The URL for this entry, relative to the root (the address to which the request is posted). E.g. for a Patient Create, the method would be "POST" and the URL would be "Patient". For a Patient Update, the method would be PUT and the URL would be "Patient/[id]". 
 
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| ifNoneMatch | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.request.ifNoneMatch For managing cache currencyDefinition If the ETag values match, return a 304 Not Modified status. See the API documentation for "Conditional Read". Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| ifModifiedSince | Σ | 0..1 | instant | There are no (further) constraints on this elementElement Id Bundle.entry.request.ifModifiedSince For managing cache currencyDefinition Only perform the operation if the last updated date matches. See the API documentation for "Conditional Read". Note: This is intended for where precisely observed times are required, typically system logs etc., and not human-reported times - for them, see date and dateTime (which can be as precise as instant, but is not required to be) below. Time zone is always required 
 
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| ifMatch | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.request.ifMatch For managing update contentionDefinition Only perform the operation if the Etag value matches. For more information, see the API section "Managing Resource Contention". Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| ifNoneExist | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.request.ifNoneExist For conditional createsDefinition Instruct the server not to perform the create if a specified resource already exists. For further information, see the API documentation for "Conditional Create". This is just the query portion of the URL - what follows the "?" (not including the "?"). Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| response | Σ I | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id Bundle.entry.response Results of execution (transaction/batch/history)Definition Indicates the results of processing the corresponding 'request' entry in the batch or transaction being responded to or what the results of an operation where when returning history. 
 
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| status | Σ | 1..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.response.status Status response code (text optional)Definition The status code returned by processing this entry. The status SHALL start with a 3 digit HTTP code (e.g. 404) and may contain the standard HTTP description associated with the status code. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| location | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.entry.response.location The location (if the operation returns a location)Definition The location header created by processing this operation, populated if the operation returns a location. see http://en.wikipedia.org/wiki/Uniform_resource_identifier 
 
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| etag | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.entry.response.etag The Etag for the resource (if relevant)Definition The Etag for the resource, if the operation for the entry produced a versioned resource (see Resource Metadata and Versioning and Managing Resource Contention). Etags match the Resource.meta.versionId. The ETag has to match the version id in the header if a resource is included. 
 
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| lastModified | Σ | 0..1 | instant | There are no (further) constraints on this elementElement Id Bundle.entry.response.lastModified Server's date time modifiedDefinition The date/time that the resource was modified on the server. This has to match the same time in the meta header (meta.lastUpdated) if a resource is included. 
 
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| outcome | Σ | 0..1 | Resource | There are no (further) constraints on this elementElement Id Bundle.entry.response.outcome OperationOutcome with hints and warnings (for batch/transaction)Definition An OperationOutcome containing hints and warnings produced as part of processing this entry in a batch or transaction. For a POST/PUT operation, this is the equivalent outcome that would be returned for prefer = operationoutcome - except that the resource is always returned whether or not the outcome is returned. This outcome is not used for error responses in batch/transaction, only for hints and warnings. In a batch operation, the error will be in Bundle.entry.response, and for transaction, there will be a single OperationOutcome instead of a bundle in the case of an error. 
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| signature | Σ | 0..1 | Signature | There are no (further) constraints on this elementElement Id Bundle.signature Digital SignatureDefinition Digital Signature - base64 encoded. XML-DSig or a JWT. A Signature holds an electronic representation of a signature and its supporting context in a FHIR accessible form. The signature may either be a cryptographic type (XML DigSig or a JWS), which is able to provide non-repudiation proof, or it may be a graphical image that represents a signature or a signature process. This element allows capturing signatures on documents, messages, transactions or even search responses, to support content-authentication, non-repudiation or other business cases. This is primarily relevant where the bundle may travel through multiple hops or via other mechanisms where HTTPS non-repudiation is insufficient. The signature could be created by the "author" of the bundle or by the originating device. Requirements around inclusion of a signature, verification of signatures and treatment of signed/non-signed bundles is implementation-environment specific. 
 
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| type | Σ | 1..* | CodingBinding | There are no (further) constraints on this elementElement Id Bundle.signature.type Indication of the reason the entity signed the object(s)Definition An indication of the reason that the entity signed this document. This may be explicitly included as part of the signature information and can be used when determining accountability for various actions concerning the document. Examples include attesting to: authorship, correct transcription, and witness of specific event. Also known as a "Commitment Type Indication". An indication of the reason that an entity signed the object.SignatureTypeCodes (preferred)Constraints 
 
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| when | Σ | 1..1 | instant | There are no (further) constraints on this elementElement Id Bundle.signature.when When the signature was createdDefinition When the digital signature was signed. This should agree with the information in the signature. 
 
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| who | Σ I | 1..1 | Reference(Device | UK Core PractitionerRole | UK Core Organization | UK Core Practitioner | UK Core RelatedPerson | UK Core Patient) | There are no (further) constraints on this elementElement Id Bundle.signature.who Who signedDefinition A reference to an application-usable description of the identity that signed (e.g. the signature used their private key). This should agree with the information in the signature. Reference(Device | UK Core PractitionerRole | UK Core Organization | UK Core Practitioner | UK Core RelatedPerson | UK Core Patient)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.who.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id Bundle.signature.who.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id Bundle.signature.who.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.who.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| onBehalfOf | Σ I | 0..1 | Reference(Device | UK Core PractitionerRole | UK Core Organization | UK Core Practitioner | UK Core RelatedPerson | UK Core Patient) | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf The party representedDefinition A reference to an application-usable description of the identity that is represented by the signature. used when the signature is on behalf of a non-signer. The party that can't sign. For example a child. Reference(Device | UK Core PractitionerRole | UK Core Organization | UK Core Practitioner | UK Core RelatedPerson | UK Core Patient)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id Bundle.signature.onBehalfOf.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| targetFormat | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.signature.targetFormat The technical format of the signed resourcesDefinition A mime type that indicates the technical format of the target resources signed by the signature. "xml", "json" and "ttl" are allowed, which describe the simple encodings described in the specification (and imply appropriate bundle support). Otherwise, mime types are legal here. The mime type of an attachment. Any valid mime type is allowed.Mime Types (required)Constraints 
 
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| sigFormat | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id Bundle.signature.sigFormat The technical format of the signatureDefinition A mime type that indicates the technical format of the signature. Important mime types are application/signature+xml for X ML DigSig, application/jose for JWS, and image/* for a graphical image of a signature, etc. Note that FHIR strings SHALL NOT exceed 1MB in size The mime type of an attachment. Any valid mime type is allowed.Mime Types (required)Constraints 
 
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| data | 0..1 | base64Binary | There are no (further) constraints on this elementElement Id Bundle.signature.data The actual signature content (XML DigSig. JWS, picture, etc.)Definition The base64 encoding of the Signature content. When signature is not recorded electronically this element would be empty. Where the signature type is an XML DigSig, the signed content is a FHIR Resource(s), the signature is of the XML form of the Resource(s) using XML-Signature (XMLDIG) "Detached Signature" form. 
 
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Examples
BARS MessageHeader - Booking-Request
Defines the constraints and extensions on the UKCore-Bundle FHIR Profile
Based on: UKCore.Release1@1.0.1/package/UKCore-Bundle
Differential View
| MessageHeader | I | MessageHeader | There are no (further) constraints on this elementElement Id MessageHeader A resource that describes a message that is exchanged between systemsDefinition The header for a message exchange that is either requesting or responding to an action. The reference(s) that are the subject of the action as well as other information related to the action are typically transmitted in a bundle in which the MessageHeader resource instance is the first resource in the bundle. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id MessageHeader.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| messageHeaderInstruction | I | 0..* | Extension(Coding) | There are no (further) constraints on this elementElement Id MessageHeader.extension:messageHeaderInstruction An extension to carry a specific instruction for receivers of the message.Alternate names extensions, user contentDefinition An extension to carry a specific instruction for receivers of the message. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-MessageHeaderInstructionConstraints 
 
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| event[x] | Σ | 1..1 | Binding | There are no (further) constraints on this elementElement Id MessageHeader.event[x] Code for the event this message represents or link to event definitionDefinition Code that identifies the event this message represents and connects it with its definition. Events defined as part of the FHIR specification have the system value "http://terminology.hl7.org/CodeSystem/message-events". Alternatively uri to the EventDefinition. Drives the behavior associated with this message. The time of the event will be found in the focus resource. The time of the message will be found in Bundle.timestamp. Message eventUKCoreMessageEvent (extensible)Constraints 
 
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| system | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].system https://fhir.nhs.uk/CodeSystem/message-events-bars | ||
| code | 1.. | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].code This will be a set of fixed values that are used to trigger use case specific processing when the bundle is received (refer to guidance for definitions etc..) booking-request | |
| eventCoding | Coding | There are no (further) constraints on this elementData Type | ||
| eventUri | uri | There are no (further) constraints on this elementData Type | ||
| destination | Σ | 1..* | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.destination Message destination application(s)Definition The destination application which the message is intended for. Indicates where message is to be sent for routing purposes. Allows verification of "am I the intended recipient". There SHOULD be at least one destination, but in some circumstances, the source system is unaware of any particular destination system. 
 
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| name | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.name Name of systemDefinition Human-readable name for the target system. May be used for routing of response and/or to support audit. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| target | Σ I | 0..1 | Reference(UK Core Device) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target Particular delivery destination within the destinationDefinition Identifies the target end system in situations where the initial message transmission is to an intermediary system. Supports multi-hop routing. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| endpoint | Σ | 1..1 | url | There are no (further) constraints on this elementElement Id MessageHeader.destination.endpoint Actual destination address or idDefinition Indicates where the message should be routed to. Identifies where to route the message. The id may be a non-resolvable URI for systems that do not use standard network-based addresses. 
 
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| receiver | Σ I | 0..1 | Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver Intended "real-world" recipient for the dataDefinition Allows data conveyed by a message to be addressed to a particular person or department when routing to a specific application isn't sufficient. Allows routing beyond just the application level. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
 | 
| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| sender | Σ I | 0..1 | Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.sender Real world sender of the messageDefinition Identifies the sending system to allow the use of a trust relationship. Allows routing beyond just the application level. Use case is for where a (trusted) sending system is responsible for multiple organizations, and therefore cannot differentiate based on source endpoint / authentication alone. Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.sender.identifier.assigner.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Reference to the Requester Organisation 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| enterer | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.enterer The source of the data entryDefinition The person or device that performed the data entry leading to this message. When there is more than one candidate, pick the most proximal to the message. Can provide other enterers in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| author | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.author The source of the decisionDefinition The logical author of the message - the person or device that decided the described event should happen. When there is more than one candidate, pick the most proximal to the MessageHeader. Can provide other authors in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
 | 
| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
 | 
| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
 | 
| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| source | Σ | 1..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.source Message source applicationDefinition The source application from which this message originated. Allows replies, supports audit. 
 
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| extension | I | 0..* | Extension | Element Id MessageHeader.source.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| myExtension | I | 0..* | Extension(Complex) | Element Id MessageHeader.source.extension:myExtension Optional Extensions ElementAlternate names extensions, user contentDefinition Optional Extension Element - found in all resources. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Extension(Complex)Extension URL https://fhir.nhs.uk/StructureDefinition/CDSSExtensionConstraints 
 
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| name | Σ | 0..1 | string | Element Id MessageHeader.source.name Name of systemDefinition Human-readable name for the source system. May be used to support audit. EMS Supplier company/ product name 
 
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| software | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.source.software Name of software running the systemDefinition May include configuration or other information useful in debugging. Supports audit and possibly interface engine behavior. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| version | Σ | 0..1 | string | Element Id MessageHeader.source.version Version of software runningDefinition Can convey versions of multiple systems in situations where a message passes through multiple hands. Supports audit and possibly interface engine behavior. EMS software version 
 
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| contact | Σ I | 0..1 | ContactPoint | There are no (further) constraints on this elementElement Id MessageHeader.source.contact Human contact for problemsDefinition An e-mail, phone, website or other contact point to use to resolve issues with message communications. Allows escalation of technical issues. 
 
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| endpoint | Σ | 1..1 | url | Element Id MessageHeader.source.endpoint Actual message source address or idDefinition Identifies the routing target to send acknowledgements to. Identifies where to send responses, may influence security permissions. The uri of the Requester’s endpoint 
 
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| responsible | Σ I | 0..1 | Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.responsible Final responsibility for eventDefinition The person or organization that accepts overall responsibility for the contents of the message. The implication is that the message event happened under the policies of the responsible party. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reason | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id MessageHeader.reason Cause of eventDefinition Coded indication of the cause for the event - indicates a reason for the occurrence of the event that is a focus of this message. Need to be able to track why resources are being changed and report in the audit log/history of the resource. May affect authorization. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. Reason for event occurrence.ExampleMessageReasonCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id MessageHeader.reason.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. BARS Event lifecycle "new", "update" 
 https://fhir.nhs.uk/CodeSystem/message-reason-bars 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | code | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| response | Σ | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.response If this is a reply to prior messageDefinition Information about the message that this message is a response to. Only present if this message is a response. 
 
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| identifier | Σ | 1..1 | id | There are no (further) constraints on this elementElement Id MessageHeader.response.identifier Id of original messageDefinition The MessageHeader.id of the message to which this message is a response. Allows receiver to know what message is being responded to. RFC 4122 
 
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| code | Σ | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.code ok | transient-error | fatal-errorDefinition Code that identifies the type of response to the message - whether it was successful or not, and whether it should be resent or not. Allows the sender of the acknowledge message to know if the request was successful or if action is needed. This is a generic response to the request message. Specific data for the response will be found in MessageHeader.focus. The kind of response to a message.ResponseType (required)Constraints 
 
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| details | Σ I | 0..1 | Reference(UK Core OperationOutcome) | There are no (further) constraints on this elementElement Id MessageHeader.response.details Specific list of hints/warnings/errorsDefinition Full details of any issues found in the message. Allows the sender of the message to determine what the specific issues are. This SHALL be contained in the bundle. If any of the issues are errors, the response code SHALL be an error. Reference(UK Core OperationOutcome)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| focus | Σ I | 0..* | Reference(Resource) | There are no (further) constraints on this elementElement Id MessageHeader.focus The actual content of the messageDefinition The actual data of the message - a reference to the root/focus class of the event. Every message event is about actual data, a single resource, that is identified in the definition of the event, and perhaps some or all linked resources. The data is defined where the transaction type is defined. The transaction data is always included in the bundle that is the full message. Only the root resource is specified. The resources it references should be contained in the bundle but are not also listed here. Multiple repetitions are allowed to cater for merges and other situations with multiple focal targets. 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.focus.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. This MUST reference the UKCore-ServiceRequest resource. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| definition | Σ | 0..1 | canonical(MessageDefinition) | There are no (further) constraints on this elementElement Id MessageHeader.definition Link to the definition for this messageDefinition Permanent link to the MessageDefinition for this message. Allows sender to define the expected contents of the message. 
 
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Hybrid View
| MessageHeader | I | MessageHeader | There are no (further) constraints on this elementElement Id MessageHeader A resource that describes a message that is exchanged between systemsDefinition The header for a message exchange that is either requesting or responding to an action. The reference(s) that are the subject of the action as well as other information related to the action are typically transmitted in a bundle in which the MessageHeader resource instance is the first resource in the bundle. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id MessageHeader.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| messageHeaderInstruction | I | 0..* | Extension(Coding) | There are no (further) constraints on this elementElement Id MessageHeader.extension:messageHeaderInstruction An extension to carry a specific instruction for receivers of the message.Alternate names extensions, user contentDefinition An extension to carry a specific instruction for receivers of the message. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-MessageHeaderInstructionConstraints 
 
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| event[x] | Σ | 1..1 | Binding | There are no (further) constraints on this elementElement Id MessageHeader.event[x] Code for the event this message represents or link to event definitionDefinition Code that identifies the event this message represents and connects it with its definition. Events defined as part of the FHIR specification have the system value "http://terminology.hl7.org/CodeSystem/message-events". Alternatively uri to the EventDefinition. Drives the behavior associated with this message. The time of the event will be found in the focus resource. The time of the message will be found in Bundle.timestamp. Message eventUKCoreMessageEvent (extensible)Constraints 
 
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| system | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].system https://fhir.nhs.uk/CodeSystem/message-events-bars | ||
| code | 1.. | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].code This will be a set of fixed values that are used to trigger use case specific processing when the bundle is received (refer to guidance for definitions etc..) booking-request | |
| eventCoding | Coding | There are no (further) constraints on this elementData Type | ||
| eventUri | uri | There are no (further) constraints on this elementData Type | ||
| destination | Σ | 1..* | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.destination Message destination application(s)Definition The destination application which the message is intended for. Indicates where message is to be sent for routing purposes. Allows verification of "am I the intended recipient". There SHOULD be at least one destination, but in some circumstances, the source system is unaware of any particular destination system. 
 
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| name | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.name Name of systemDefinition Human-readable name for the target system. May be used for routing of response and/or to support audit. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| target | Σ I | 0..1 | Reference(UK Core Device) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target Particular delivery destination within the destinationDefinition Identifies the target end system in situations where the initial message transmission is to an intermediary system. Supports multi-hop routing. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| endpoint | Σ | 1..1 | url | There are no (further) constraints on this elementElement Id MessageHeader.destination.endpoint Actual destination address or idDefinition Indicates where the message should be routed to. Identifies where to route the message. The id may be a non-resolvable URI for systems that do not use standard network-based addresses. 
 
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| receiver | Σ I | 0..1 | Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver Intended "real-world" recipient for the dataDefinition Allows data conveyed by a message to be addressed to a particular person or department when routing to a specific application isn't sufficient. Allows routing beyond just the application level. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
 | 
| sender | Σ I | 0..1 | Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.sender Real world sender of the messageDefinition Identifies the sending system to allow the use of a trust relationship. Allows routing beyond just the application level. Use case is for where a (trusted) sending system is responsible for multiple organizations, and therefore cannot differentiate based on source endpoint / authentication alone. Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
 | 
| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
 | 
| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
 | 
| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
 | 
| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
 | 
| reference | Σ I | 1..1 | string | Element Id MessageHeader.sender.identifier.assigner.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Reference to the Requester Organisation 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| enterer | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.enterer The source of the data entryDefinition The person or device that performed the data entry leading to this message. When there is more than one candidate, pick the most proximal to the message. Can provide other enterers in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| author | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.author The source of the decisionDefinition The logical author of the message - the person or device that decided the described event should happen. When there is more than one candidate, pick the most proximal to the MessageHeader. Can provide other authors in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| source | Σ | 1..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.source Message source applicationDefinition The source application from which this message originated. Allows replies, supports audit. 
 
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| extension | I | 0..* | Extension | Element Id MessageHeader.source.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| myExtension | I | 0..* | Extension(Complex) | Element Id MessageHeader.source.extension:myExtension Optional Extensions ElementAlternate names extensions, user contentDefinition Optional Extension Element - found in all resources. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Extension(Complex)Extension URL https://fhir.nhs.uk/StructureDefinition/CDSSExtensionConstraints 
 
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| name | Σ | 0..1 | string | Element Id MessageHeader.source.name Name of systemDefinition Human-readable name for the source system. May be used to support audit. EMS Supplier company/ product name 
 
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| software | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.source.software Name of software running the systemDefinition May include configuration or other information useful in debugging. Supports audit and possibly interface engine behavior. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| version | Σ | 0..1 | string | Element Id MessageHeader.source.version Version of software runningDefinition Can convey versions of multiple systems in situations where a message passes through multiple hands. Supports audit and possibly interface engine behavior. EMS software version 
 
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| contact | Σ I | 0..1 | ContactPoint | There are no (further) constraints on this elementElement Id MessageHeader.source.contact Human contact for problemsDefinition An e-mail, phone, website or other contact point to use to resolve issues with message communications. Allows escalation of technical issues. 
 
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| endpoint | Σ | 1..1 | url | Element Id MessageHeader.source.endpoint Actual message source address or idDefinition Identifies the routing target to send acknowledgements to. Identifies where to send responses, may influence security permissions. The uri of the Requester’s endpoint 
 
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| responsible | Σ I | 0..1 | Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.responsible Final responsibility for eventDefinition The person or organization that accepts overall responsibility for the contents of the message. The implication is that the message event happened under the policies of the responsible party. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reason | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id MessageHeader.reason Cause of eventDefinition Coded indication of the cause for the event - indicates a reason for the occurrence of the event that is a focus of this message. Need to be able to track why resources are being changed and report in the audit log/history of the resource. May affect authorization. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. Reason for event occurrence.ExampleMessageReasonCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id MessageHeader.reason.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. BARS Event lifecycle "new", "update" 
 https://fhir.nhs.uk/CodeSystem/message-reason-bars 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | code | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| response | Σ | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.response If this is a reply to prior messageDefinition Information about the message that this message is a response to. Only present if this message is a response. 
 
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| identifier | Σ | 1..1 | id | There are no (further) constraints on this elementElement Id MessageHeader.response.identifier Id of original messageDefinition The MessageHeader.id of the message to which this message is a response. Allows receiver to know what message is being responded to. RFC 4122 
 
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| code | Σ | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.code ok | transient-error | fatal-errorDefinition Code that identifies the type of response to the message - whether it was successful or not, and whether it should be resent or not. Allows the sender of the acknowledge message to know if the request was successful or if action is needed. This is a generic response to the request message. Specific data for the response will be found in MessageHeader.focus. The kind of response to a message.ResponseType (required)Constraints 
 
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| details | Σ I | 0..1 | Reference(UK Core OperationOutcome) | There are no (further) constraints on this elementElement Id MessageHeader.response.details Specific list of hints/warnings/errorsDefinition Full details of any issues found in the message. Allows the sender of the message to determine what the specific issues are. This SHALL be contained in the bundle. If any of the issues are errors, the response code SHALL be an error. Reference(UK Core OperationOutcome)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| focus | Σ I | 0..* | Reference(Resource) | There are no (further) constraints on this elementElement Id MessageHeader.focus The actual content of the messageDefinition The actual data of the message - a reference to the root/focus class of the event. Every message event is about actual data, a single resource, that is identified in the definition of the event, and perhaps some or all linked resources. The data is defined where the transaction type is defined. The transaction data is always included in the bundle that is the full message. Only the root resource is specified. The resources it references should be contained in the bundle but are not also listed here. Multiple repetitions are allowed to cater for merges and other situations with multiple focal targets. 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.focus.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. This MUST reference the UKCore-ServiceRequest resource. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| definition | Σ | 0..1 | canonical(MessageDefinition) | There are no (further) constraints on this elementElement Id MessageHeader.definition Link to the definition for this messageDefinition Permanent link to the MessageDefinition for this message. Allows sender to define the expected contents of the message. 
 
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Snapshot View
| MessageHeader | I | MessageHeader | There are no (further) constraints on this elementElement Id MessageHeader A resource that describes a message that is exchanged between systemsDefinition The header for a message exchange that is either requesting or responding to an action. The reference(s) that are the subject of the action as well as other information related to the action are typically transmitted in a bundle in which the MessageHeader resource instance is the first resource in the bundle. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id MessageHeader.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| messageHeaderInstruction | I | 0..* | Extension(Coding) | There are no (further) constraints on this elementElement Id MessageHeader.extension:messageHeaderInstruction An extension to carry a specific instruction for receivers of the message.Alternate names extensions, user contentDefinition An extension to carry a specific instruction for receivers of the message. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-MessageHeaderInstructionConstraints 
 
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| event[x] | Σ | 1..1 | Binding | There are no (further) constraints on this elementElement Id MessageHeader.event[x] Code for the event this message represents or link to event definitionDefinition Code that identifies the event this message represents and connects it with its definition. Events defined as part of the FHIR specification have the system value "http://terminology.hl7.org/CodeSystem/message-events". Alternatively uri to the EventDefinition. Drives the behavior associated with this message. The time of the event will be found in the focus resource. The time of the message will be found in Bundle.timestamp. Message eventUKCoreMessageEvent (extensible)Constraints 
 
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| system | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].system https://fhir.nhs.uk/CodeSystem/message-events-bars | ||
| code | 1.. | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].code This will be a set of fixed values that are used to trigger use case specific processing when the bundle is received (refer to guidance for definitions etc..) booking-request | |
| eventCoding | Coding | There are no (further) constraints on this elementData Type | ||
| eventUri | uri | There are no (further) constraints on this elementData Type | ||
| destination | Σ | 1..* | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.destination Message destination application(s)Definition The destination application which the message is intended for. Indicates where message is to be sent for routing purposes. Allows verification of "am I the intended recipient". There SHOULD be at least one destination, but in some circumstances, the source system is unaware of any particular destination system. 
 
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| name | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.name Name of systemDefinition Human-readable name for the target system. May be used for routing of response and/or to support audit. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| target | Σ I | 0..1 | Reference(UK Core Device) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target Particular delivery destination within the destinationDefinition Identifies the target end system in situations where the initial message transmission is to an intermediary system. Supports multi-hop routing. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| endpoint | Σ | 1..1 | url | There are no (further) constraints on this elementElement Id MessageHeader.destination.endpoint Actual destination address or idDefinition Indicates where the message should be routed to. Identifies where to route the message. The id may be a non-resolvable URI for systems that do not use standard network-based addresses. 
 
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| receiver | Σ I | 0..1 | Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver Intended "real-world" recipient for the dataDefinition Allows data conveyed by a message to be addressed to a particular person or department when routing to a specific application isn't sufficient. Allows routing beyond just the application level. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| sender | Σ I | 0..1 | Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.sender Real world sender of the messageDefinition Identifies the sending system to allow the use of a trust relationship. Allows routing beyond just the application level. Use case is for where a (trusted) sending system is responsible for multiple organizations, and therefore cannot differentiate based on source endpoint / authentication alone. Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.sender.identifier.assigner.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Reference to the Requester Organisation 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| enterer | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.enterer The source of the data entryDefinition The person or device that performed the data entry leading to this message. When there is more than one candidate, pick the most proximal to the message. Can provide other enterers in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
 | 
| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
 | 
| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| author | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.author The source of the decisionDefinition The logical author of the message - the person or device that decided the described event should happen. When there is more than one candidate, pick the most proximal to the MessageHeader. Can provide other authors in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| source | Σ | 1..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.source Message source applicationDefinition The source application from which this message originated. Allows replies, supports audit. 
 
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| extension | I | 0..* | Extension | Element Id MessageHeader.source.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| myExtension | I | 0..* | Extension(Complex) | Element Id MessageHeader.source.extension:myExtension Optional Extensions ElementAlternate names extensions, user contentDefinition Optional Extension Element - found in all resources. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Extension(Complex)Extension URL https://fhir.nhs.uk/StructureDefinition/CDSSExtensionConstraints 
 
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| name | Σ | 0..1 | string | Element Id MessageHeader.source.name Name of systemDefinition Human-readable name for the source system. May be used to support audit. EMS Supplier company/ product name 
 
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| software | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.source.software Name of software running the systemDefinition May include configuration or other information useful in debugging. Supports audit and possibly interface engine behavior. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| version | Σ | 0..1 | string | Element Id MessageHeader.source.version Version of software runningDefinition Can convey versions of multiple systems in situations where a message passes through multiple hands. Supports audit and possibly interface engine behavior. EMS software version 
 
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| contact | Σ I | 0..1 | ContactPoint | There are no (further) constraints on this elementElement Id MessageHeader.source.contact Human contact for problemsDefinition An e-mail, phone, website or other contact point to use to resolve issues with message communications. Allows escalation of technical issues. 
 
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| endpoint | Σ | 1..1 | url | Element Id MessageHeader.source.endpoint Actual message source address or idDefinition Identifies the routing target to send acknowledgements to. Identifies where to send responses, may influence security permissions. The uri of the Requester’s endpoint 
 
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| responsible | Σ I | 0..1 | Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.responsible Final responsibility for eventDefinition The person or organization that accepts overall responsibility for the contents of the message. The implication is that the message event happened under the policies of the responsible party. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reason | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id MessageHeader.reason Cause of eventDefinition Coded indication of the cause for the event - indicates a reason for the occurrence of the event that is a focus of this message. Need to be able to track why resources are being changed and report in the audit log/history of the resource. May affect authorization. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. Reason for event occurrence.ExampleMessageReasonCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id MessageHeader.reason.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. BARS Event lifecycle "new", "update" 
 https://fhir.nhs.uk/CodeSystem/message-reason-bars 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | code | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| response | Σ | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.response If this is a reply to prior messageDefinition Information about the message that this message is a response to. Only present if this message is a response. 
 
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| identifier | Σ | 1..1 | id | There are no (further) constraints on this elementElement Id MessageHeader.response.identifier Id of original messageDefinition The MessageHeader.id of the message to which this message is a response. Allows receiver to know what message is being responded to. RFC 4122 
 
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| code | Σ | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.code ok | transient-error | fatal-errorDefinition Code that identifies the type of response to the message - whether it was successful or not, and whether it should be resent or not. Allows the sender of the acknowledge message to know if the request was successful or if action is needed. This is a generic response to the request message. Specific data for the response will be found in MessageHeader.focus. The kind of response to a message.ResponseType (required)Constraints 
 
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| details | Σ I | 0..1 | Reference(UK Core OperationOutcome) | There are no (further) constraints on this elementElement Id MessageHeader.response.details Specific list of hints/warnings/errorsDefinition Full details of any issues found in the message. Allows the sender of the message to determine what the specific issues are. This SHALL be contained in the bundle. If any of the issues are errors, the response code SHALL be an error. Reference(UK Core OperationOutcome)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
 | 
| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| focus | Σ I | 0..* | Reference(Resource) | There are no (further) constraints on this elementElement Id MessageHeader.focus The actual content of the messageDefinition The actual data of the message - a reference to the root/focus class of the event. Every message event is about actual data, a single resource, that is identified in the definition of the event, and perhaps some or all linked resources. The data is defined where the transaction type is defined. The transaction data is always included in the bundle that is the full message. Only the root resource is specified. The resources it references should be contained in the bundle but are not also listed here. Multiple repetitions are allowed to cater for merges and other situations with multiple focal targets. 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.focus.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. This MUST reference the UKCore-ServiceRequest resource. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
 | 
| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| definition | Σ | 0..1 | canonical(MessageDefinition) | There are no (further) constraints on this elementElement Id MessageHeader.definition Link to the definition for this messageDefinition Permanent link to the MessageDefinition for this message. Allows sender to define the expected contents of the message. 
 
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Examples
BARS MessageHeader - ServiceRequest-Request
Defines the constraints and extensions on the UKCore-Bundle FHIR Profile
Based on: UKCore.Release1@1.0.1/package/UKCore-Bundle
Differential View
| MessageHeader | I | MessageHeader | There are no (further) constraints on this elementElement Id MessageHeader A resource that describes a message that is exchanged between systemsDefinition The header for a message exchange that is either requesting or responding to an action. The reference(s) that are the subject of the action as well as other information related to the action are typically transmitted in a bundle in which the MessageHeader resource instance is the first resource in the bundle. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id MessageHeader.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| messageHeaderInstruction | I | 0..* | Extension(Coding) | There are no (further) constraints on this elementElement Id MessageHeader.extension:messageHeaderInstruction An extension to carry a specific instruction for receivers of the message.Alternate names extensions, user contentDefinition An extension to carry a specific instruction for receivers of the message. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-MessageHeaderInstructionConstraints 
 
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| event[x] | Σ | 1..1 | Binding | There are no (further) constraints on this elementElement Id MessageHeader.event[x] Code for the event this message represents or link to event definitionDefinition Code that identifies the event this message represents and connects it with its definition. Events defined as part of the FHIR specification have the system value "http://terminology.hl7.org/CodeSystem/message-events". Alternatively uri to the EventDefinition. Drives the behavior associated with this message. The time of the event will be found in the focus resource. The time of the message will be found in Bundle.timestamp. Message eventUKCoreMessageEvent (extensible)Constraints 
 
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| system | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].system https://fhir.nhs.uk/CodeSystem/message-events-bars | ||
| code | 1.. | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].code This will be a set of fixed values that are used to trigger use case specific processing when the bundle is received (refer to guidance for definitions etc..) servicerequest-request | |
| eventCoding | Coding | There are no (further) constraints on this elementData Type | ||
| eventUri | uri | There are no (further) constraints on this elementData Type | ||
| destination | Σ | 1..* | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.destination Message destination application(s)Definition The destination application which the message is intended for. Indicates where message is to be sent for routing purposes. Allows verification of "am I the intended recipient". There SHOULD be at least one destination, but in some circumstances, the source system is unaware of any particular destination system. 
 
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| name | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.name Name of systemDefinition Human-readable name for the target system. May be used for routing of response and/or to support audit. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| target | Σ I | 0..1 | Reference(UK Core Device) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target Particular delivery destination within the destinationDefinition Identifies the target end system in situations where the initial message transmission is to an intermediary system. Supports multi-hop routing. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
 | 
| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| endpoint | Σ | 1..1 | url | There are no (further) constraints on this elementElement Id MessageHeader.destination.endpoint Actual destination address or idDefinition Indicates where the message should be routed to. Identifies where to route the message. The id may be a non-resolvable URI for systems that do not use standard network-based addresses. 
 
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| receiver | Σ I | 0..1 | Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver Intended "real-world" recipient for the dataDefinition Allows data conveyed by a message to be addressed to a particular person or department when routing to a specific application isn't sufficient. Allows routing beyond just the application level. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
 | 
| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
 | 
| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
 | 
| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
 | 
| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| sender | Σ I | 0..1 | Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.sender Real world sender of the messageDefinition Identifies the sending system to allow the use of a trust relationship. Allows routing beyond just the application level. Use case is for where a (trusted) sending system is responsible for multiple organizations, and therefore cannot differentiate based on source endpoint / authentication alone. Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.sender.identifier.assigner.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Reference to the Requester Organisation 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| enterer | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.enterer The source of the data entryDefinition The person or device that performed the data entry leading to this message. When there is more than one candidate, pick the most proximal to the message. Can provide other enterers in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| author | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.author The source of the decisionDefinition The logical author of the message - the person or device that decided the described event should happen. When there is more than one candidate, pick the most proximal to the MessageHeader. Can provide other authors in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| source | Σ | 1..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.source Message source applicationDefinition The source application from which this message originated. Allows replies, supports audit. 
 
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| extension | I | 0..* | Extension | Element Id MessageHeader.source.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| myExtension | I | 0..* | Extension(Complex) | Element Id MessageHeader.source.extension:myExtension Optional Extensions ElementAlternate names extensions, user contentDefinition Optional Extension Element - found in all resources. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Extension(Complex)Extension URL https://fhir.nhs.uk/StructureDefinition/CDSSExtensionConstraints 
 
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| name | Σ | 0..1 | string | Element Id MessageHeader.source.name Name of systemDefinition Human-readable name for the source system. May be used to support audit. EMS Supplier company/ product name 
 
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| software | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.source.software Name of software running the systemDefinition May include configuration or other information useful in debugging. Supports audit and possibly interface engine behavior. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| version | Σ | 0..1 | string | Element Id MessageHeader.source.version Version of software runningDefinition Can convey versions of multiple systems in situations where a message passes through multiple hands. Supports audit and possibly interface engine behavior. EMS software version 
 
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| contact | Σ I | 0..1 | ContactPoint | There are no (further) constraints on this elementElement Id MessageHeader.source.contact Human contact for problemsDefinition An e-mail, phone, website or other contact point to use to resolve issues with message communications. Allows escalation of technical issues. 
 
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| endpoint | Σ | 1..1 | url | Element Id MessageHeader.source.endpoint Actual message source address or idDefinition Identifies the routing target to send acknowledgements to. Identifies where to send responses, may influence security permissions. The uri of the Requester’s endpoint 
 
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| responsible | Σ I | 0..1 | Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.responsible Final responsibility for eventDefinition The person or organization that accepts overall responsibility for the contents of the message. The implication is that the message event happened under the policies of the responsible party. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reason | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id MessageHeader.reason Cause of eventDefinition Coded indication of the cause for the event - indicates a reason for the occurrence of the event that is a focus of this message. Need to be able to track why resources are being changed and report in the audit log/history of the resource. May affect authorization. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. Reason for event occurrence.ExampleMessageReasonCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id MessageHeader.reason.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. BARS Event lifecycle "new", "update" 
 https://fhir.nhs.uk/CodeSystem/message-reason-bars 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | code | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| response | Σ | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.response If this is a reply to prior messageDefinition Information about the message that this message is a response to. Only present if this message is a response. 
 
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| identifier | Σ | 1..1 | id | There are no (further) constraints on this elementElement Id MessageHeader.response.identifier Id of original messageDefinition The MessageHeader.id of the message to which this message is a response. Allows receiver to know what message is being responded to. RFC 4122 
 
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| code | Σ | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.code ok | transient-error | fatal-errorDefinition Code that identifies the type of response to the message - whether it was successful or not, and whether it should be resent or not. Allows the sender of the acknowledge message to know if the request was successful or if action is needed. This is a generic response to the request message. Specific data for the response will be found in MessageHeader.focus. The kind of response to a message.ResponseType (required)Constraints 
 
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| details | Σ I | 0..1 | Reference(UK Core OperationOutcome) | There are no (further) constraints on this elementElement Id MessageHeader.response.details Specific list of hints/warnings/errorsDefinition Full details of any issues found in the message. Allows the sender of the message to determine what the specific issues are. This SHALL be contained in the bundle. If any of the issues are errors, the response code SHALL be an error. Reference(UK Core OperationOutcome)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| focus | Σ I | 0..* | Reference(Resource) | There are no (further) constraints on this elementElement Id MessageHeader.focus The actual content of the messageDefinition The actual data of the message - a reference to the root/focus class of the event. Every message event is about actual data, a single resource, that is identified in the definition of the event, and perhaps some or all linked resources. The data is defined where the transaction type is defined. The transaction data is always included in the bundle that is the full message. Only the root resource is specified. The resources it references should be contained in the bundle but are not also listed here. Multiple repetitions are allowed to cater for merges and other situations with multiple focal targets. 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.focus.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. This MUST reference the UKCore-ServiceRequest resource. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| definition | Σ | 0..1 | canonical(MessageDefinition) | There are no (further) constraints on this elementElement Id MessageHeader.definition Link to the definition for this messageDefinition Permanent link to the MessageDefinition for this message. Allows sender to define the expected contents of the message. 
 
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Hybrid View
| MessageHeader | I | MessageHeader | There are no (further) constraints on this elementElement Id MessageHeader A resource that describes a message that is exchanged between systemsDefinition The header for a message exchange that is either requesting or responding to an action. The reference(s) that are the subject of the action as well as other information related to the action are typically transmitted in a bundle in which the MessageHeader resource instance is the first resource in the bundle. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id MessageHeader.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| messageHeaderInstruction | I | 0..* | Extension(Coding) | There are no (further) constraints on this elementElement Id MessageHeader.extension:messageHeaderInstruction An extension to carry a specific instruction for receivers of the message.Alternate names extensions, user contentDefinition An extension to carry a specific instruction for receivers of the message. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-MessageHeaderInstructionConstraints 
 
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| event[x] | Σ | 1..1 | Binding | There are no (further) constraints on this elementElement Id MessageHeader.event[x] Code for the event this message represents or link to event definitionDefinition Code that identifies the event this message represents and connects it with its definition. Events defined as part of the FHIR specification have the system value "http://terminology.hl7.org/CodeSystem/message-events". Alternatively uri to the EventDefinition. Drives the behavior associated with this message. The time of the event will be found in the focus resource. The time of the message will be found in Bundle.timestamp. Message eventUKCoreMessageEvent (extensible)Constraints 
 
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| system | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].system https://fhir.nhs.uk/CodeSystem/message-events-bars | ||
| code | 1.. | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].code This will be a set of fixed values that are used to trigger use case specific processing when the bundle is received (refer to guidance for definitions etc..) servicerequest-request | |
| eventCoding | Coding | There are no (further) constraints on this elementData Type | ||
| eventUri | uri | There are no (further) constraints on this elementData Type | ||
| destination | Σ | 1..* | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.destination Message destination application(s)Definition The destination application which the message is intended for. Indicates where message is to be sent for routing purposes. Allows verification of "am I the intended recipient". There SHOULD be at least one destination, but in some circumstances, the source system is unaware of any particular destination system. 
 
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| name | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.name Name of systemDefinition Human-readable name for the target system. May be used for routing of response and/or to support audit. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| target | Σ I | 0..1 | Reference(UK Core Device) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target Particular delivery destination within the destinationDefinition Identifies the target end system in situations where the initial message transmission is to an intermediary system. Supports multi-hop routing. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| endpoint | Σ | 1..1 | url | There are no (further) constraints on this elementElement Id MessageHeader.destination.endpoint Actual destination address or idDefinition Indicates where the message should be routed to. Identifies where to route the message. The id may be a non-resolvable URI for systems that do not use standard network-based addresses. 
 
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| receiver | Σ I | 0..1 | Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver Intended "real-world" recipient for the dataDefinition Allows data conveyed by a message to be addressed to a particular person or department when routing to a specific application isn't sufficient. Allows routing beyond just the application level. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| sender | Σ I | 0..1 | Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.sender Real world sender of the messageDefinition Identifies the sending system to allow the use of a trust relationship. Allows routing beyond just the application level. Use case is for where a (trusted) sending system is responsible for multiple organizations, and therefore cannot differentiate based on source endpoint / authentication alone. Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.sender.identifier.assigner.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Reference to the Requester Organisation 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| enterer | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.enterer The source of the data entryDefinition The person or device that performed the data entry leading to this message. When there is more than one candidate, pick the most proximal to the message. Can provide other enterers in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| author | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.author The source of the decisionDefinition The logical author of the message - the person or device that decided the described event should happen. When there is more than one candidate, pick the most proximal to the MessageHeader. Can provide other authors in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| source | Σ | 1..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.source Message source applicationDefinition The source application from which this message originated. Allows replies, supports audit. 
 
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| extension | I | 0..* | Extension | Element Id MessageHeader.source.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| myExtension | I | 0..* | Extension(Complex) | Element Id MessageHeader.source.extension:myExtension Optional Extensions ElementAlternate names extensions, user contentDefinition Optional Extension Element - found in all resources. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Extension(Complex)Extension URL https://fhir.nhs.uk/StructureDefinition/CDSSExtensionConstraints 
 
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| name | Σ | 0..1 | string | Element Id MessageHeader.source.name Name of systemDefinition Human-readable name for the source system. May be used to support audit. EMS Supplier company/ product name 
 
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| software | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.source.software Name of software running the systemDefinition May include configuration or other information useful in debugging. Supports audit and possibly interface engine behavior. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| version | Σ | 0..1 | string | Element Id MessageHeader.source.version Version of software runningDefinition Can convey versions of multiple systems in situations where a message passes through multiple hands. Supports audit and possibly interface engine behavior. EMS software version 
 
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| contact | Σ I | 0..1 | ContactPoint | There are no (further) constraints on this elementElement Id MessageHeader.source.contact Human contact for problemsDefinition An e-mail, phone, website or other contact point to use to resolve issues with message communications. Allows escalation of technical issues. 
 
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| endpoint | Σ | 1..1 | url | Element Id MessageHeader.source.endpoint Actual message source address or idDefinition Identifies the routing target to send acknowledgements to. Identifies where to send responses, may influence security permissions. The uri of the Requester’s endpoint 
 
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| responsible | Σ I | 0..1 | Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.responsible Final responsibility for eventDefinition The person or organization that accepts overall responsibility for the contents of the message. The implication is that the message event happened under the policies of the responsible party. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reason | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id MessageHeader.reason Cause of eventDefinition Coded indication of the cause for the event - indicates a reason for the occurrence of the event that is a focus of this message. Need to be able to track why resources are being changed and report in the audit log/history of the resource. May affect authorization. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. Reason for event occurrence.ExampleMessageReasonCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id MessageHeader.reason.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. BARS Event lifecycle "new", "update" 
 https://fhir.nhs.uk/CodeSystem/message-reason-bars 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | code | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| response | Σ | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.response If this is a reply to prior messageDefinition Information about the message that this message is a response to. Only present if this message is a response. 
 
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| identifier | Σ | 1..1 | id | There are no (further) constraints on this elementElement Id MessageHeader.response.identifier Id of original messageDefinition The MessageHeader.id of the message to which this message is a response. Allows receiver to know what message is being responded to. RFC 4122 
 
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| code | Σ | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.code ok | transient-error | fatal-errorDefinition Code that identifies the type of response to the message - whether it was successful or not, and whether it should be resent or not. Allows the sender of the acknowledge message to know if the request was successful or if action is needed. This is a generic response to the request message. Specific data for the response will be found in MessageHeader.focus. The kind of response to a message.ResponseType (required)Constraints 
 
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| details | Σ I | 0..1 | Reference(UK Core OperationOutcome) | There are no (further) constraints on this elementElement Id MessageHeader.response.details Specific list of hints/warnings/errorsDefinition Full details of any issues found in the message. Allows the sender of the message to determine what the specific issues are. This SHALL be contained in the bundle. If any of the issues are errors, the response code SHALL be an error. Reference(UK Core OperationOutcome)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| focus | Σ I | 0..* | Reference(Resource) | There are no (further) constraints on this elementElement Id MessageHeader.focus The actual content of the messageDefinition The actual data of the message - a reference to the root/focus class of the event. Every message event is about actual data, a single resource, that is identified in the definition of the event, and perhaps some or all linked resources. The data is defined where the transaction type is defined. The transaction data is always included in the bundle that is the full message. Only the root resource is specified. The resources it references should be contained in the bundle but are not also listed here. Multiple repetitions are allowed to cater for merges and other situations with multiple focal targets. 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.focus.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. This MUST reference the UKCore-ServiceRequest resource. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| definition | Σ | 0..1 | canonical(MessageDefinition) | There are no (further) constraints on this elementElement Id MessageHeader.definition Link to the definition for this messageDefinition Permanent link to the MessageDefinition for this message. Allows sender to define the expected contents of the message. 
 
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Snapshot View
| MessageHeader | I | MessageHeader | There are no (further) constraints on this elementElement Id MessageHeader A resource that describes a message that is exchanged between systemsDefinition The header for a message exchange that is either requesting or responding to an action. The reference(s) that are the subject of the action as well as other information related to the action are typically transmitted in a bundle in which the MessageHeader resource instance is the first resource in the bundle. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id MessageHeader.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| messageHeaderInstruction | I | 0..* | Extension(Coding) | There are no (further) constraints on this elementElement Id MessageHeader.extension:messageHeaderInstruction An extension to carry a specific instruction for receivers of the message.Alternate names extensions, user contentDefinition An extension to carry a specific instruction for receivers of the message. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-MessageHeaderInstructionConstraints 
 
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| event[x] | Σ | 1..1 | Binding | There are no (further) constraints on this elementElement Id MessageHeader.event[x] Code for the event this message represents or link to event definitionDefinition Code that identifies the event this message represents and connects it with its definition. Events defined as part of the FHIR specification have the system value "http://terminology.hl7.org/CodeSystem/message-events". Alternatively uri to the EventDefinition. Drives the behavior associated with this message. The time of the event will be found in the focus resource. The time of the message will be found in Bundle.timestamp. Message eventUKCoreMessageEvent (extensible)Constraints 
 
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| system | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].system https://fhir.nhs.uk/CodeSystem/message-events-bars | ||
| code | 1.. | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].code This will be a set of fixed values that are used to trigger use case specific processing when the bundle is received (refer to guidance for definitions etc..) servicerequest-request | |
| eventCoding | Coding | There are no (further) constraints on this elementData Type | ||
| eventUri | uri | There are no (further) constraints on this elementData Type | ||
| destination | Σ | 1..* | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.destination Message destination application(s)Definition The destination application which the message is intended for. Indicates where message is to be sent for routing purposes. Allows verification of "am I the intended recipient". There SHOULD be at least one destination, but in some circumstances, the source system is unaware of any particular destination system. 
 
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| name | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.name Name of systemDefinition Human-readable name for the target system. May be used for routing of response and/or to support audit. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| target | Σ I | 0..1 | Reference(UK Core Device) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target Particular delivery destination within the destinationDefinition Identifies the target end system in situations where the initial message transmission is to an intermediary system. Supports multi-hop routing. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| endpoint | Σ | 1..1 | url | There are no (further) constraints on this elementElement Id MessageHeader.destination.endpoint Actual destination address or idDefinition Indicates where the message should be routed to. Identifies where to route the message. The id may be a non-resolvable URI for systems that do not use standard network-based addresses. 
 
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| receiver | Σ I | 0..1 | Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver Intended "real-world" recipient for the dataDefinition Allows data conveyed by a message to be addressed to a particular person or department when routing to a specific application isn't sufficient. Allows routing beyond just the application level. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| sender | Σ I | 0..1 | Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.sender Real world sender of the messageDefinition Identifies the sending system to allow the use of a trust relationship. Allows routing beyond just the application level. Use case is for where a (trusted) sending system is responsible for multiple organizations, and therefore cannot differentiate based on source endpoint / authentication alone. Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.sender.identifier.assigner.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Reference to the Requester Organisation 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| enterer | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.enterer The source of the data entryDefinition The person or device that performed the data entry leading to this message. When there is more than one candidate, pick the most proximal to the message. Can provide other enterers in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
 | 
| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
 | 
| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
 | 
| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| author | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.author The source of the decisionDefinition The logical author of the message - the person or device that decided the described event should happen. When there is more than one candidate, pick the most proximal to the MessageHeader. Can provide other authors in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| source | Σ | 1..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.source Message source applicationDefinition The source application from which this message originated. Allows replies, supports audit. 
 
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| extension | I | 0..* | Extension | Element Id MessageHeader.source.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| myExtension | I | 0..* | Extension(Complex) | Element Id MessageHeader.source.extension:myExtension Optional Extensions ElementAlternate names extensions, user contentDefinition Optional Extension Element - found in all resources. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Extension(Complex)Extension URL https://fhir.nhs.uk/StructureDefinition/CDSSExtensionConstraints 
 
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| name | Σ | 0..1 | string | Element Id MessageHeader.source.name Name of systemDefinition Human-readable name for the source system. May be used to support audit. EMS Supplier company/ product name 
 
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| software | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.source.software Name of software running the systemDefinition May include configuration or other information useful in debugging. Supports audit and possibly interface engine behavior. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| version | Σ | 0..1 | string | Element Id MessageHeader.source.version Version of software runningDefinition Can convey versions of multiple systems in situations where a message passes through multiple hands. Supports audit and possibly interface engine behavior. EMS software version 
 
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| contact | Σ I | 0..1 | ContactPoint | There are no (further) constraints on this elementElement Id MessageHeader.source.contact Human contact for problemsDefinition An e-mail, phone, website or other contact point to use to resolve issues with message communications. Allows escalation of technical issues. 
 
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| endpoint | Σ | 1..1 | url | Element Id MessageHeader.source.endpoint Actual message source address or idDefinition Identifies the routing target to send acknowledgements to. Identifies where to send responses, may influence security permissions. The uri of the Requester’s endpoint 
 
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| responsible | Σ I | 0..1 | Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.responsible Final responsibility for eventDefinition The person or organization that accepts overall responsibility for the contents of the message. The implication is that the message event happened under the policies of the responsible party. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reason | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id MessageHeader.reason Cause of eventDefinition Coded indication of the cause for the event - indicates a reason for the occurrence of the event that is a focus of this message. Need to be able to track why resources are being changed and report in the audit log/history of the resource. May affect authorization. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. Reason for event occurrence.ExampleMessageReasonCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id MessageHeader.reason.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. BARS Event lifecycle "new", "update" 
 https://fhir.nhs.uk/CodeSystem/message-reason-bars 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | code | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| response | Σ | 0..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.response If this is a reply to prior messageDefinition Information about the message that this message is a response to. Only present if this message is a response. 
 
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| identifier | Σ | 1..1 | id | There are no (further) constraints on this elementElement Id MessageHeader.response.identifier Id of original messageDefinition The MessageHeader.id of the message to which this message is a response. Allows receiver to know what message is being responded to. RFC 4122 
 
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| code | Σ | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.code ok | transient-error | fatal-errorDefinition Code that identifies the type of response to the message - whether it was successful or not, and whether it should be resent or not. Allows the sender of the acknowledge message to know if the request was successful or if action is needed. This is a generic response to the request message. Specific data for the response will be found in MessageHeader.focus. The kind of response to a message.ResponseType (required)Constraints 
 
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| details | Σ I | 0..1 | Reference(UK Core OperationOutcome) | There are no (further) constraints on this elementElement Id MessageHeader.response.details Specific list of hints/warnings/errorsDefinition Full details of any issues found in the message. Allows the sender of the message to determine what the specific issues are. This SHALL be contained in the bundle. If any of the issues are errors, the response code SHALL be an error. Reference(UK Core OperationOutcome)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| focus | Σ I | 0..* | Reference(Resource) | There are no (further) constraints on this elementElement Id MessageHeader.focus The actual content of the messageDefinition The actual data of the message - a reference to the root/focus class of the event. Every message event is about actual data, a single resource, that is identified in the definition of the event, and perhaps some or all linked resources. The data is defined where the transaction type is defined. The transaction data is always included in the bundle that is the full message. Only the root resource is specified. The resources it references should be contained in the bundle but are not also listed here. Multiple repetitions are allowed to cater for merges and other situations with multiple focal targets. 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.focus.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. This MUST reference the UKCore-ServiceRequest resource. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| definition | Σ | 0..1 | canonical(MessageDefinition) | There are no (further) constraints on this elementElement Id MessageHeader.definition Link to the definition for this messageDefinition Permanent link to the MessageDefinition for this message. Allows sender to define the expected contents of the message. 
 
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Examples
BARS MessageHeader - ServiceRequest-Response
Defines the constraints and extensions on the UKCore-Bundle FHIR Profile
Based on: UKCore.Release1@1.0.1/package/UKCore-Bundle
Differential View
| MessageHeader | I | MessageHeader | There are no (further) constraints on this elementElement Id MessageHeader A resource that describes a message that is exchanged between systemsDefinition The header for a message exchange that is either requesting or responding to an action. The reference(s) that are the subject of the action as well as other information related to the action are typically transmitted in a bundle in which the MessageHeader resource instance is the first resource in the bundle. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id MessageHeader.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| messageHeaderInstruction | I | 0..* | Extension(Coding) | There are no (further) constraints on this elementElement Id MessageHeader.extension:messageHeaderInstruction An extension to carry a specific instruction for receivers of the message.Alternate names extensions, user contentDefinition An extension to carry a specific instruction for receivers of the message. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-MessageHeaderInstructionConstraints 
 
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| event[x] | Σ | 1..1 | Binding | There are no (further) constraints on this elementElement Id MessageHeader.event[x] Code for the event this message represents or link to event definitionDefinition Code that identifies the event this message represents and connects it with its definition. Events defined as part of the FHIR specification have the system value "http://terminology.hl7.org/CodeSystem/message-events". Alternatively uri to the EventDefinition. Drives the behavior associated with this message. The time of the event will be found in the focus resource. The time of the message will be found in Bundle.timestamp. Message eventUKCoreMessageEvent (extensible)Constraints 
 
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| system | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].system https://fhir.nhs.uk/CodeSystem/message-events-bars | ||
| code | 1.. | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].code This will be a set of fixed values that are used to trigger use case specific processing when the bundle is received (refer to guidance for definitions etc..) servicerequest-response | |
| eventCoding | Coding | There are no (further) constraints on this elementData Type | ||
| eventUri | uri | There are no (further) constraints on this elementData Type | ||
| destination | Σ | 1..* | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.destination Message destination application(s)Definition The destination application which the message is intended for. Indicates where message is to be sent for routing purposes. Allows verification of "am I the intended recipient". There SHOULD be at least one destination, but in some circumstances, the source system is unaware of any particular destination system. 
 
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| name | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.name Name of systemDefinition Human-readable name for the target system. May be used for routing of response and/or to support audit. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| target | Σ I | 0..1 | Reference(UK Core Device) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target Particular delivery destination within the destinationDefinition Identifies the target end system in situations where the initial message transmission is to an intermediary system. Supports multi-hop routing. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| endpoint | Σ | 1..1 | url | There are no (further) constraints on this elementElement Id MessageHeader.destination.endpoint Actual destination address or idDefinition Indicates where the message should be routed to. Identifies where to route the message. The id may be a non-resolvable URI for systems that do not use standard network-based addresses. 
 
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| receiver | Σ I | 0..1 | Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver Intended "real-world" recipient for the dataDefinition Allows data conveyed by a message to be addressed to a particular person or department when routing to a specific application isn't sufficient. Allows routing beyond just the application level. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| sender | Σ I | 0..1 | Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.sender Real world sender of the messageDefinition Identifies the sending system to allow the use of a trust relationship. Allows routing beyond just the application level. Use case is for where a (trusted) sending system is responsible for multiple organizations, and therefore cannot differentiate based on source endpoint / authentication alone. Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.sender.identifier.assigner.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Reference to the Requester Organisation 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| enterer | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.enterer The source of the data entryDefinition The person or device that performed the data entry leading to this message. When there is more than one candidate, pick the most proximal to the message. Can provide other enterers in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| author | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.author The source of the decisionDefinition The logical author of the message - the person or device that decided the described event should happen. When there is more than one candidate, pick the most proximal to the MessageHeader. Can provide other authors in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| source | Σ | 1..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.source Message source applicationDefinition The source application from which this message originated. Allows replies, supports audit. 
 
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| extension | I | 0..* | Extension | Element Id MessageHeader.source.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| myExtension | I | 0..* | Extension(Complex) | Element Id MessageHeader.source.extension:myExtension Optional Extensions ElementAlternate names extensions, user contentDefinition Optional Extension Element - found in all resources. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Extension(Complex)Extension URL https://fhir.nhs.uk/StructureDefinition/CDSSExtensionConstraints 
 
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| name | Σ | 0..1 | string | Element Id MessageHeader.source.name Name of systemDefinition Human-readable name for the source system. May be used to support audit. EMS Supplier company/ product name 
 
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| software | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.source.software Name of software running the systemDefinition May include configuration or other information useful in debugging. Supports audit and possibly interface engine behavior. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| version | Σ | 0..1 | string | Element Id MessageHeader.source.version Version of software runningDefinition Can convey versions of multiple systems in situations where a message passes through multiple hands. Supports audit and possibly interface engine behavior. EMS software version 
 
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| contact | Σ I | 0..1 | ContactPoint | There are no (further) constraints on this elementElement Id MessageHeader.source.contact Human contact for problemsDefinition An e-mail, phone, website or other contact point to use to resolve issues with message communications. Allows escalation of technical issues. 
 
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| endpoint | Σ | 1..1 | url | Element Id MessageHeader.source.endpoint Actual message source address or idDefinition Identifies the routing target to send acknowledgements to. Identifies where to send responses, may influence security permissions. The uri of the Requester’s endpoint 
 
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| responsible | Σ I | 0..1 | Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.responsible Final responsibility for eventDefinition The person or organization that accepts overall responsibility for the contents of the message. The implication is that the message event happened under the policies of the responsible party. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reason | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id MessageHeader.reason Cause of eventDefinition Coded indication of the cause for the event - indicates a reason for the occurrence of the event that is a focus of this message. Need to be able to track why resources are being changed and report in the audit log/history of the resource. May affect authorization. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. Reason for event occurrence.ExampleMessageReasonCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id MessageHeader.reason.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. BARS Event lifecycle "new", "update" 
 https://fhir.nhs.uk/CodeSystem/message-reason-bars 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | code | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| response | Σ | 1..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.response If this is a reply to prior messageDefinition Information about the message that this message is a response to. Only present if this message is a response. 
 
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| identifier | Σ | 1..1 | id | There are no (further) constraints on this elementElement Id MessageHeader.response.identifier Id of original messageDefinition The MessageHeader.id of the message to which this message is a response. Allows receiver to know what message is being responded to. RFC 4122 
 
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| code | Σ | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.code ok | transient-error | fatal-errorDefinition Code that identifies the type of response to the message - whether it was successful or not, and whether it should be resent or not. Allows the sender of the acknowledge message to know if the request was successful or if action is needed. This is a generic response to the request message. Specific data for the response will be found in MessageHeader.focus. The kind of response to a message.ResponseType (required)Constraints 
 
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| details | Σ I | 0..1 | Reference(UK Core OperationOutcome) | There are no (further) constraints on this elementElement Id MessageHeader.response.details Specific list of hints/warnings/errorsDefinition Full details of any issues found in the message. Allows the sender of the message to determine what the specific issues are. This SHALL be contained in the bundle. If any of the issues are errors, the response code SHALL be an error. Reference(UK Core OperationOutcome)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| focus | Σ I | 0..* | Reference(Resource) | There are no (further) constraints on this elementElement Id MessageHeader.focus The actual content of the messageDefinition The actual data of the message - a reference to the root/focus class of the event. Every message event is about actual data, a single resource, that is identified in the definition of the event, and perhaps some or all linked resources. The data is defined where the transaction type is defined. The transaction data is always included in the bundle that is the full message. Only the root resource is specified. The resources it references should be contained in the bundle but are not also listed here. Multiple repetitions are allowed to cater for merges and other situations with multiple focal targets. 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.focus.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. This MUST reference the UKCore-ServiceRequest resource. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| definition | Σ | 0..1 | canonical(MessageDefinition) | There are no (further) constraints on this elementElement Id MessageHeader.definition Link to the definition for this messageDefinition Permanent link to the MessageDefinition for this message. Allows sender to define the expected contents of the message. 
 
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Hybrid View
| MessageHeader | I | MessageHeader | There are no (further) constraints on this elementElement Id MessageHeader A resource that describes a message that is exchanged between systemsDefinition The header for a message exchange that is either requesting or responding to an action. The reference(s) that are the subject of the action as well as other information related to the action are typically transmitted in a bundle in which the MessageHeader resource instance is the first resource in the bundle. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id MessageHeader.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| messageHeaderInstruction | I | 0..* | Extension(Coding) | There are no (further) constraints on this elementElement Id MessageHeader.extension:messageHeaderInstruction An extension to carry a specific instruction for receivers of the message.Alternate names extensions, user contentDefinition An extension to carry a specific instruction for receivers of the message. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-MessageHeaderInstructionConstraints 
 
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| event[x] | Σ | 1..1 | Binding | There are no (further) constraints on this elementElement Id MessageHeader.event[x] Code for the event this message represents or link to event definitionDefinition Code that identifies the event this message represents and connects it with its definition. Events defined as part of the FHIR specification have the system value "http://terminology.hl7.org/CodeSystem/message-events". Alternatively uri to the EventDefinition. Drives the behavior associated with this message. The time of the event will be found in the focus resource. The time of the message will be found in Bundle.timestamp. Message eventUKCoreMessageEvent (extensible)Constraints 
 
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| system | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].system https://fhir.nhs.uk/CodeSystem/message-events-bars | ||
| code | 1.. | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].code This will be a set of fixed values that are used to trigger use case specific processing when the bundle is received (refer to guidance for definitions etc..) servicerequest-response | |
| eventCoding | Coding | There are no (further) constraints on this elementData Type | ||
| eventUri | uri | There are no (further) constraints on this elementData Type | ||
| destination | Σ | 1..* | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.destination Message destination application(s)Definition The destination application which the message is intended for. Indicates where message is to be sent for routing purposes. Allows verification of "am I the intended recipient". There SHOULD be at least one destination, but in some circumstances, the source system is unaware of any particular destination system. 
 
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| name | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.name Name of systemDefinition Human-readable name for the target system. May be used for routing of response and/or to support audit. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| target | Σ I | 0..1 | Reference(UK Core Device) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target Particular delivery destination within the destinationDefinition Identifies the target end system in situations where the initial message transmission is to an intermediary system. Supports multi-hop routing. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| endpoint | Σ | 1..1 | url | There are no (further) constraints on this elementElement Id MessageHeader.destination.endpoint Actual destination address or idDefinition Indicates where the message should be routed to. Identifies where to route the message. The id may be a non-resolvable URI for systems that do not use standard network-based addresses. 
 
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| receiver | Σ I | 0..1 | Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver Intended "real-world" recipient for the dataDefinition Allows data conveyed by a message to be addressed to a particular person or department when routing to a specific application isn't sufficient. Allows routing beyond just the application level. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| sender | Σ I | 0..1 | Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.sender Real world sender of the messageDefinition Identifies the sending system to allow the use of a trust relationship. Allows routing beyond just the application level. Use case is for where a (trusted) sending system is responsible for multiple organizations, and therefore cannot differentiate based on source endpoint / authentication alone. Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.sender.identifier.assigner.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Reference to the Requester Organisation 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| enterer | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.enterer The source of the data entryDefinition The person or device that performed the data entry leading to this message. When there is more than one candidate, pick the most proximal to the message. Can provide other enterers in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| author | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.author The source of the decisionDefinition The logical author of the message - the person or device that decided the described event should happen. When there is more than one candidate, pick the most proximal to the MessageHeader. Can provide other authors in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| source | Σ | 1..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.source Message source applicationDefinition The source application from which this message originated. Allows replies, supports audit. 
 
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| extension | I | 0..* | Extension | Element Id MessageHeader.source.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| myExtension | I | 0..* | Extension(Complex) | Element Id MessageHeader.source.extension:myExtension Optional Extensions ElementAlternate names extensions, user contentDefinition Optional Extension Element - found in all resources. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Extension(Complex)Extension URL https://fhir.nhs.uk/StructureDefinition/CDSSExtensionConstraints 
 
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| name | Σ | 0..1 | string | Element Id MessageHeader.source.name Name of systemDefinition Human-readable name for the source system. May be used to support audit. EMS Supplier company/ product name 
 
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| software | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.source.software Name of software running the systemDefinition May include configuration or other information useful in debugging. Supports audit and possibly interface engine behavior. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| version | Σ | 0..1 | string | Element Id MessageHeader.source.version Version of software runningDefinition Can convey versions of multiple systems in situations where a message passes through multiple hands. Supports audit and possibly interface engine behavior. EMS software version 
 
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| contact | Σ I | 0..1 | ContactPoint | There are no (further) constraints on this elementElement Id MessageHeader.source.contact Human contact for problemsDefinition An e-mail, phone, website or other contact point to use to resolve issues with message communications. Allows escalation of technical issues. 
 
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| endpoint | Σ | 1..1 | url | Element Id MessageHeader.source.endpoint Actual message source address or idDefinition Identifies the routing target to send acknowledgements to. Identifies where to send responses, may influence security permissions. The uri of the Requester’s endpoint 
 
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| responsible | Σ I | 0..1 | Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.responsible Final responsibility for eventDefinition The person or organization that accepts overall responsibility for the contents of the message. The implication is that the message event happened under the policies of the responsible party. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reason | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id MessageHeader.reason Cause of eventDefinition Coded indication of the cause for the event - indicates a reason for the occurrence of the event that is a focus of this message. Need to be able to track why resources are being changed and report in the audit log/history of the resource. May affect authorization. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. Reason for event occurrence.ExampleMessageReasonCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id MessageHeader.reason.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. BARS Event lifecycle "new", "update" 
 https://fhir.nhs.uk/CodeSystem/message-reason-bars 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | code | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| response | Σ | 1..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.response If this is a reply to prior messageDefinition Information about the message that this message is a response to. Only present if this message is a response. 
 
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| identifier | Σ | 1..1 | id | There are no (further) constraints on this elementElement Id MessageHeader.response.identifier Id of original messageDefinition The MessageHeader.id of the message to which this message is a response. Allows receiver to know what message is being responded to. RFC 4122 
 
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| code | Σ | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.code ok | transient-error | fatal-errorDefinition Code that identifies the type of response to the message - whether it was successful or not, and whether it should be resent or not. Allows the sender of the acknowledge message to know if the request was successful or if action is needed. This is a generic response to the request message. Specific data for the response will be found in MessageHeader.focus. The kind of response to a message.ResponseType (required)Constraints 
 
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| details | Σ I | 0..1 | Reference(UK Core OperationOutcome) | There are no (further) constraints on this elementElement Id MessageHeader.response.details Specific list of hints/warnings/errorsDefinition Full details of any issues found in the message. Allows the sender of the message to determine what the specific issues are. This SHALL be contained in the bundle. If any of the issues are errors, the response code SHALL be an error. Reference(UK Core OperationOutcome)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| focus | Σ I | 0..* | Reference(Resource) | There are no (further) constraints on this elementElement Id MessageHeader.focus The actual content of the messageDefinition The actual data of the message - a reference to the root/focus class of the event. Every message event is about actual data, a single resource, that is identified in the definition of the event, and perhaps some or all linked resources. The data is defined where the transaction type is defined. The transaction data is always included in the bundle that is the full message. Only the root resource is specified. The resources it references should be contained in the bundle but are not also listed here. Multiple repetitions are allowed to cater for merges and other situations with multiple focal targets. 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.focus.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. This MUST reference the UKCore-ServiceRequest resource. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| definition | Σ | 0..1 | canonical(MessageDefinition) | There are no (further) constraints on this elementElement Id MessageHeader.definition Link to the definition for this messageDefinition Permanent link to the MessageDefinition for this message. Allows sender to define the expected contents of the message. 
 
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Snapshot View
| MessageHeader | I | MessageHeader | There are no (further) constraints on this elementElement Id MessageHeader A resource that describes a message that is exchanged between systemsDefinition The header for a message exchange that is either requesting or responding to an action. The reference(s) that are the subject of the action as well as other information related to the action are typically transmitted in a bundle in which the MessageHeader resource instance is the first resource in the bundle. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id MessageHeader.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| messageHeaderInstruction | I | 0..* | Extension(Coding) | There are no (further) constraints on this elementElement Id MessageHeader.extension:messageHeaderInstruction An extension to carry a specific instruction for receivers of the message.Alternate names extensions, user contentDefinition An extension to carry a specific instruction for receivers of the message. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-MessageHeaderInstructionConstraints 
 
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| event[x] | Σ | 1..1 | Binding | There are no (further) constraints on this elementElement Id MessageHeader.event[x] Code for the event this message represents or link to event definitionDefinition Code that identifies the event this message represents and connects it with its definition. Events defined as part of the FHIR specification have the system value "http://terminology.hl7.org/CodeSystem/message-events". Alternatively uri to the EventDefinition. Drives the behavior associated with this message. The time of the event will be found in the focus resource. The time of the message will be found in Bundle.timestamp. Message eventUKCoreMessageEvent (extensible)Constraints 
 
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| system | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].system https://fhir.nhs.uk/CodeSystem/message-events-bars | ||
| code | 1.. | Fixed Value | There are no (further) constraints on this elementElement Id MessageHeader.event[x].code This will be a set of fixed values that are used to trigger use case specific processing when the bundle is received (refer to guidance for definitions etc..) servicerequest-response | |
| eventCoding | Coding | There are no (further) constraints on this elementData Type | ||
| eventUri | uri | There are no (further) constraints on this elementData Type | ||
| destination | Σ | 1..* | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.destination Message destination application(s)Definition The destination application which the message is intended for. Indicates where message is to be sent for routing purposes. Allows verification of "am I the intended recipient". There SHOULD be at least one destination, but in some circumstances, the source system is unaware of any particular destination system. 
 
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| name | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.name Name of systemDefinition Human-readable name for the target system. May be used for routing of response and/or to support audit. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| target | Σ I | 0..1 | Reference(UK Core Device) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target Particular delivery destination within the destinationDefinition Identifies the target end system in situations where the initial message transmission is to an intermediary system. Supports multi-hop routing. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.target.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| endpoint | Σ | 1..1 | url | There are no (further) constraints on this elementElement Id MessageHeader.destination.endpoint Actual destination address or idDefinition Indicates where the message should be routed to. Identifies where to route the message. The id may be a non-resolvable URI for systems that do not use standard network-based addresses. 
 
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| receiver | Σ I | 0..1 | Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver Intended "real-world" recipient for the dataDefinition Allows data conveyed by a message to be addressed to a particular person or department when routing to a specific application isn't sufficient. Allows routing beyond just the application level. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core Organization | UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.destination.receiver.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| sender | Σ I | 0..1 | Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.sender Real world sender of the messageDefinition Identifies the sending system to allow the use of a trust relationship. Allows routing beyond just the application level. Use case is for where a (trusted) sending system is responsible for multiple organizations, and therefore cannot differentiate based on source endpoint / authentication alone. Reference(UK Core PractitionerRole | UK Core Organization | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 1..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| reference | Σ I | 1..1 | string | Element Id MessageHeader.sender.identifier.assigner.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Reference to the Requester Organisation 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.identifier.assigner.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.sender.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| enterer | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.enterer The source of the data entryDefinition The person or device that performed the data entry leading to this message. When there is more than one candidate, pick the most proximal to the message. Can provide other enterers in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
 | 
| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
 | 
| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
 | 
| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.enterer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.enterer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| author | Σ I | 0..1 | Reference(UK Core Practitioner | UK Core PractitionerRole) | There are no (further) constraints on this elementElement Id MessageHeader.author The source of the decisionDefinition The logical author of the message - the person or device that decided the described event should happen. When there is more than one candidate, pick the most proximal to the MessageHeader. Can provide other authors in extensions. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Practitioner | UK Core PractitionerRole)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.author.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.author.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| source | Σ | 1..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.source Message source applicationDefinition The source application from which this message originated. Allows replies, supports audit. 
 
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| extension | I | 0..* | Extension | Element Id MessageHeader.source.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| myExtension | I | 0..* | Extension(Complex) | Element Id MessageHeader.source.extension:myExtension Optional Extensions ElementAlternate names extensions, user contentDefinition Optional Extension Element - found in all resources. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Extension(Complex)Extension URL https://fhir.nhs.uk/StructureDefinition/CDSSExtensionConstraints 
 
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| name | Σ | 0..1 | string | Element Id MessageHeader.source.name Name of systemDefinition Human-readable name for the source system. May be used to support audit. EMS Supplier company/ product name 
 
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| software | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.source.software Name of software running the systemDefinition May include configuration or other information useful in debugging. Supports audit and possibly interface engine behavior. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| version | Σ | 0..1 | string | Element Id MessageHeader.source.version Version of software runningDefinition Can convey versions of multiple systems in situations where a message passes through multiple hands. Supports audit and possibly interface engine behavior. EMS software version 
 
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| contact | Σ I | 0..1 | ContactPoint | There are no (further) constraints on this elementElement Id MessageHeader.source.contact Human contact for problemsDefinition An e-mail, phone, website or other contact point to use to resolve issues with message communications. Allows escalation of technical issues. 
 
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| endpoint | Σ | 1..1 | url | Element Id MessageHeader.source.endpoint Actual message source address or idDefinition Identifies the routing target to send acknowledgements to. Identifies where to send responses, may influence security permissions. The uri of the Requester’s endpoint 
 
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| responsible | Σ I | 0..1 | Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner) | There are no (further) constraints on this elementElement Id MessageHeader.responsible Final responsibility for eventDefinition The person or organization that accepts overall responsibility for the contents of the message. The implication is that the message event happened under the policies of the responsible party. Need to know for audit/traceback requirements and possibly for authorization. Usually only for the request but can be used in a response. Reference(UK Core Organization | UK Core PractitionerRole | UK Core Practitioner)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.responsible.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.responsible.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reason | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id MessageHeader.reason Cause of eventDefinition Coded indication of the cause for the event - indicates a reason for the occurrence of the event that is a focus of this message. Need to be able to track why resources are being changed and report in the audit log/history of the resource. May affect authorization. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. Reason for event occurrence.ExampleMessageReasonCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id MessageHeader.reason.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. BARS Event lifecycle "new", "update" 
 https://fhir.nhs.uk/CodeSystem/message-reason-bars 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | code | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id MessageHeader.reason.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.reason.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| response | Σ | 1..1 | BackboneElement | There are no (further) constraints on this elementElement Id MessageHeader.response If this is a reply to prior messageDefinition Information about the message that this message is a response to. Only present if this message is a response. 
 
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| identifier | Σ | 1..1 | id | There are no (further) constraints on this elementElement Id MessageHeader.response.identifier Id of original messageDefinition The MessageHeader.id of the message to which this message is a response. Allows receiver to know what message is being responded to. RFC 4122 
 
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| code | Σ | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.code ok | transient-error | fatal-errorDefinition Code that identifies the type of response to the message - whether it was successful or not, and whether it should be resent or not. Allows the sender of the acknowledge message to know if the request was successful or if action is needed. This is a generic response to the request message. Specific data for the response will be found in MessageHeader.focus. The kind of response to a message.ResponseType (required)Constraints 
 
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| details | Σ I | 0..1 | Reference(UK Core OperationOutcome) | There are no (further) constraints on this elementElement Id MessageHeader.response.details Specific list of hints/warnings/errorsDefinition Full details of any issues found in the message. Allows the sender of the message to determine what the specific issues are. This SHALL be contained in the bundle. If any of the issues are errors, the response code SHALL be an error. Reference(UK Core OperationOutcome)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
 | 
| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.response.details.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.response.details.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
 | 
| focus | Σ I | 0..* | Reference(Resource) | There are no (further) constraints on this elementElement Id MessageHeader.focus The actual content of the messageDefinition The actual data of the message - a reference to the root/focus class of the event. Every message event is about actual data, a single resource, that is identified in the definition of the event, and perhaps some or all linked resources. The data is defined where the transaction type is defined. The transaction data is always included in the bundle that is the full message. Only the root resource is specified. The resources it references should be contained in the bundle but are not also listed here. Multiple repetitions are allowed to cater for merges and other situations with multiple focal targets. 
 
 | 
| reference | Σ I | 1..1 | string | Element Id MessageHeader.focus.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. This MUST reference the UKCore-ServiceRequest resource. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id MessageHeader.focus.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id MessageHeader.focus.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| definition | Σ | 0..1 | canonical(MessageDefinition) | There are no (further) constraints on this elementElement Id MessageHeader.definition Link to the definition for this messageDefinition Permanent link to the MessageDefinition for this message. Allows sender to define the expected contents of the message. 
 
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Examples
BARS ServiceRequest-Request Referral
Defines the constraints and extensions on the UKCore-Bundle FHIR Profile
Based on: UKCore.Release1@1.0.1/package/UKCore-Bundle
Differential View
| ServiceRequest | I | ServiceRequest | There are no (further) constraints on this elementElement Id ServiceRequest A request for a service to be performedAlternate names diagnostic request, referral, referral request, transfer of care requestDefinition A record of a request for service such as diagnostic investigations, treatments, or operations to be performed. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id ServiceRequest.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| sourceOfServiceRequest | I | 0..1 | Extension(CodeableConcept) | There are no (further) constraints on this elementElement Id ServiceRequest.extension:sourceOfServiceRequest This represents the source of referralAlternate names extensions, user contentDefinition This represents the source of referral. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-SourceOfServiceRequestConstraints 
 
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| identifier | Σ | 0..* | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.identifier Identifiers assigned to this orderDefinition Identifiers assigned to this order instance by the orderer and/or the receiver and/or order fulfiller. The identifier.type element is used to distinguish between the identifiers assigned by the orderer (known as the 'Placer' in HL7 v2) and the producer of the observations in response to the order (known as the 'Filler' in HL7 v2). For further discussion and examples see the resource notes section below. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
 | 
| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| instantiatesCanonical | Σ | 0..* | canonical(ActivityDefinition | PlanDefinition) | There are no (further) constraints on this elementElement Id ServiceRequest.instantiatesCanonical Instantiates FHIR protocol or definitionDefinition The URL pointing to a FHIR-defined protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest. Note: This is a business identifier, not a resource identifier (see discussion). It is best practice for the identifier to only appear on a single resource instance, however business practices may occasionally dictate that multiple resource instances with the same identifier can exist - possibly even with different resource types. For example, multiple Patient and a Person resource instance might share the same social insurance number. canonical(ActivityDefinition | PlanDefinition)Constraints 
 
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| instantiatesUri | Σ | 0..* | uri | There are no (further) constraints on this elementElement Id ServiceRequest.instantiatesUri Instantiates external protocol or definitionDefinition The URL pointing to an externally maintained protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest. This might be an HTML page, PDF, etc. or could just be a non-resolvable URI identifier. 
 
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| basedOn | Σ I | 0..* | Reference(UK Core CarePlan | UK Core MedicationRequest | UK Core ServiceRequest) | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn What request fulfillsAlternate names fulfillsDefinition Plan/proposal/order fulfilled by this request. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core CarePlan | UK Core MedicationRequest | UK Core ServiceRequest)Constraints 
 
 | 
| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
 | 
| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
 | 
| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
 | 
| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
 | 
| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
 | 
| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
 | 
| replaces | Σ I | 0..* | Reference(UK Core ServiceRequest) | There are no (further) constraints on this elementElement Id ServiceRequest.replaces What request replacesAlternate names supersedes, prior, renewed orderDefinition The request takes the place of the referenced completed or terminated request(s). References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core ServiceRequest)Constraints 
 
 | 
| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
 | 
| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
 | 
| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
 | 
| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
 | 
| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| requisition | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.requisition Composite Request IDAlternate names grouperId, groupIdentifierDefinition A shared identifier common to all service requests that were authorized more or less simultaneously by a single author, representing the composite or group identifier. Some business processes need to know if multiple items were ordered as part of the same "requisition" for billing or other purposes. Requests are linked either by a "basedOn" relationship (i.e. one request is fulfilling another) or by having a common requisition. Requests that are part of the same requisition are generally treated independently from the perspective of changing their state or maintaining them after initial creation. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| status | Σ ?! | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.status draft | active | on-hold | revoked | completed | entered-in-error | unknownDefinition The status of the order. The status is generally fully in the control of the requester - they determine whether the order is draft or active and, after it has been activated, competed, cancelled or suspended. States relating to the activities of the performer are reflected on either the corresponding event (see Event Pattern for general discussion) or using the Task resource. The status of a service order.RequestStatus (required)Constraints 
 
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| intent | Σ ?! | 1..1 | codeBindingFixed Value | Element Id ServiceRequest.intent proposal | plan | directive | order | original-order | reflex-order | filler-order | instance-order | optionDefinition Whether the request is a proposal, plan, an original order or a reflex order. This element is labeled as a modifier because the intent alters when and how the resource is actually applicable. The kind of service request.RequestIntent (required)Constraints 
 plan 
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| category | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.category Classification of serviceDefinition A code that classifies the service for searching, sorting and display purposes (e.g. "Surgical Procedure"). Used for filtering what service request are retrieved and displayed. There may be multiple axis of categorization depending on the context or use case for retrieving or displaying the resource. The level of granularity is defined by the category concepts in the value set. Classification of the requested service.ServiceRequestCategoryCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id ServiceRequest.category.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. 
 https://fhir.nhs.uk/CodeSystem/message-category-servicerequest 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | codeFixed Value | Element Id ServiceRequest.category.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 referral 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| priority | Σ | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.priority routine | urgent | asap | statDefinition Indicates how quickly the ServiceRequest should be addressed with respect to other requests. Note that FHIR strings SHALL NOT exceed 1MB in size Identifies the level of importance to be assigned to actioning the request.RequestPriority (required)Constraints 
 
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| doNotPerform | Σ ?! | 0..1 | boolean | There are no (further) constraints on this elementElement Id ServiceRequest.doNotPerform True if service/procedure should not be performedDefinition Set this to true if the record is saying that the service/procedure should NOT be performed. Used for do not ambulate, do not elevate head of bed, do not flush NG tube, do not take blood pressure on a certain arm, etc. In general, only the code and timeframe will be present, though occasional additional qualifiers such as body site or even performer could be included to narrow the scope of the prohibition. If the ServiceRequest.code and ServiceRequest.doNotPerform both contain negation, that will reinforce prohibition and should not have a double negative interpretation. 
 
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| code | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.code What is being requested/orderedAlternate names service requestedDefinition A code that identifies a particular service (i.e., procedure, diagnostic investigation, or panel of investigations) that have been requested. Many laboratory and radiology procedure codes embed the specimen/organ system in the test order name, for example, serum or serum/plasma glucose, or a chest x-ray. The specimen might not be recorded separately from the test code. A set of codes that define a procedure or a procedure with explicit context. Selected from the SNOMED CT UK coding system.UKCoreProcedureCode (preferred)Constraints 
 
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| orderDetail | Σ I | 0..* | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.orderDetail Additional order informationAlternate names detailed instructionsDefinition Additional details and instructions about the how the services are to be delivered. For example, and order for a urinary catheter may have an order detail for an external or indwelling catheter, or an order for a bandage may require additional instructions specifying how the bandage should be applied. For information from the medical record intended to support the delivery of the requested services, use the  Codified order entry details which are based on order context.ServiceRequestOrderDetailsCodes (example)Constraints 
 
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| quantity[x] | Σ | 0..1 | There are no (further) constraints on this elementElement Id ServiceRequest.quantity[x] Service amountDefinition An amount of service being requested which can be a quantity ( for example $1,500 home modification), a ratio ( for example, 20 half day visits per month), or a range (2.0 to 1.8 Gy per fraction). When ordering a service the number of service items may need to be specified separately from the the service item. 
 
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| quantityQuantity | Quantity | There are no (further) constraints on this elementData Type | ||
| quantityRatio | Ratio | There are no (further) constraints on this elementData Type | ||
| quantityRange | Range | There are no (further) constraints on this elementData Type | ||
| subject | Σ I | 1..1 | Reference(UK Core Patient) | Element Id ServiceRequest.subject Individual or Entity the service is ordered forDefinition On whom or what the service is to be performed. This is usually a human patient, but can also be requested on animals, groups of humans or animals, devices such as dialysis machines, or even locations (typically for environmental scans). References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| encounter | Σ I | 0..1 | Reference(UK Core Encounter) | Element Id ServiceRequest.encounter Encounter in which the request was createdAlternate names contextDefinition An encounter that provides additional information about the healthcare context in which this request is made. Encounter context 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| occurrence[x] | Σ | 0..1 | Element Id ServiceRequest.occurrence[x] When service should occurAlternate names scheduleDefinition The date/time at which the requested service should occur. Validation Breach Time/Call back breach time 
 
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| occurrencePeriod | Period | Data Type | ||
| asNeeded[x] | Σ | 0..1 | There are no (further) constraints on this elementElement Id ServiceRequest.asNeeded[x] Preconditions for serviceDefinition If a CodeableConcept is present, it indicates the pre-condition for performing the service. For example "pain", "on flare-up", etc. A coded concept identifying the pre-condition that should hold prior to performing a procedure. For example "pain", "on flare-up", etc.SNOMEDCTMedicationAsNeededReasonCodes (example)Constraints 
 
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| asNeededBoolean | boolean | There are no (further) constraints on this elementData Type | ||
| asNeededCodeableConcept | CodeableConcept | There are no (further) constraints on this elementData Type | ||
| authoredOn | Σ | 1..1 | dateTime | Element Id ServiceRequest.authoredOn Date request signedAlternate names orderedOnDefinition When the request transitioned to being actionable. ReferralDateTime 
 
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| requester | Σ I | 0..1 | Reference(UK Core Device | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson) | Element Id ServiceRequest.requester Who/what is requesting serviceAlternate names author, ordererDefinition The individual who initiated the request and has responsibility for its activation. Participant Reference(UK Core Device | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson)Constraints 
 
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| reference | Σ I | 0..1 | string | Element Id ServiceRequest.requester.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Organisation 
 
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| type | Σ | 0..1 | uriBinding | Element Id ServiceRequest.requester.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Service Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requester.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| performerType | Σ | 0..1 | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.performerType Performer roleAlternate names specialtyDefinition Desired type of performer for doing the requested service. This is a role, not a participation type. In other words, does not describe the task but describes the capacity. For example, “compounding pharmacy”, “psychiatrist” or “internal referral”. Indicates specific responsibility of an individual within the care team, such as "Primary physician", "Team coordinator", "Caregiver", etc.ParticipantRoles (example)Constraints 
 
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| performer | Σ I | 0..* | Reference(UK Core CareTeam | UK Core Device | UK Core HealthcareService | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson) | Element Id ServiceRequest.performer Requested performerAlternate names request recipientDefinition The desired performer for doing the requested service. For example, the surgeon, dermatopathologist, endoscopist, etc. Referral To Reference(UK Core CareTeam | UK Core Device | UK Core HealthcareService | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| locationCode | Σ | 0..* | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.locationCode Requested locationDefinition The preferred location(s) where the procedure should actually happen in coded or free text form. E.g. at home or nursing day care center. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. A location type where services are delivered.v3.ServiceDeliveryLocationRoleType (example)Constraints 
 
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| locationReference | Σ I | 0..* | Reference(UK Core Location) | Element Id ServiceRequest.locationReference Requested locationDefinition A reference to the the preferred location(s) where the procedure should actually happen. E.g. at home or nursing day care center. Incident location 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reasonCode | Σ | 0..* | CodeableConceptBinding | Element Id ServiceRequest.reasonCode Explanation/Justification for procedure or serviceDefinition An explanation or justification for why this service is being requested in coded or textual form.   This is often for billing purposes.  May relate to the resources referred to in  Reason for referral/Next activity/Clinical Urgency of Referral A set of codes that define a reason for a service request.UKCoreServiceRequestReasonCode (extensible)Constraints 
 
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| coding | Σ | 0..* | Coding | Element Id ServiceRequest.reasonCode.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Proprietary Triage Outcome code system 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonCode.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| reasonReference | Σ I | 0..* | Reference(UK Core Condition | UK Core DiagnosticReport | UK Core DocumentReference | UK Core Observation) | Element Id ServiceRequest.reasonReference Explanation/Justification for service or serviceDefinition Indicates another resource that provides a justification for why this service is being requested.   May relate to the resources referred to in  Chief concern Reference(UK Core Condition | UK Core DiagnosticReport | UK Core DocumentReference | UK Core Observation)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| insurance | I | 0..* | Reference(Coverage | ClaimResponse) | There are no (further) constraints on this elementElement Id ServiceRequest.insurance Associated insurance coverageDefinition Insurance plans, coverage extensions, pre-authorizations and/or pre-determinations that may be needed for delivering the requested service. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(Coverage | ClaimResponse)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| supportingInfo | I | 0..* | Reference(Resource) | Element Id ServiceRequest.supportingInfo Additional clinical informationAlternate names Ask at order entry question, AOEDefinition Additional clinical information about the patient or specimen that may influence the services or their interpretations. This information includes diagnosis, clinical findings and other observations. In laboratory ordering these are typically referred to as "ask at order entry questions (AOEs)". This includes observations explicitly requested by the producer (filler) to provide context or supporting information needed to complete the order. For example, reporting the amount of inspired oxygen for blood gas measurements. Rejected Services/patient choice (QuestionnaireResponse), Secondary concern (Condition) 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| specimen | Σ I | 0..* | Reference(UK Core Specimen) | There are no (further) constraints on this elementElement Id ServiceRequest.specimen Procedure SamplesDefinition One or more specimens that the laboratory procedure will use. Many diagnostic procedures need a specimen, but the request itself is not actually about the specimen. This element is for when the diagnostic is requested on already existing specimens and the request points to the specimen it applies to. Conversely, if the request is entered first with an unknown specimen, then the Specimen resource points to the ServiceRequest. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| bodySite | Σ | 0..* | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.bodySite Location on BodyAlternate names locationDefinition Anatomic location where the procedure should be performed. This is the target site. Knowing where the procedure is performed is important for tracking if multiple sites are possible. Only used if not implicit in the code found in ServiceRequest.code. If the use case requires BodySite to be handled as a separate resource instead of an inline coded element (e.g. to identify and track separately) then use the standard extension procedure-targetBodyStructure. A set of codes that define an anatomical or acquired body structure site. Selected from the SNOMED CT UK coding system.UKCoreBodySite (extensible)Constraints 
 
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| note | 0..* | Annotation | There are no (further) constraints on this elementElement Id ServiceRequest.note CommentsDefinition Any other notes and comments made about the service request. For example, internal billing notes. For systems that do not have structured annotations, they can simply communicate a single annotation with no author or time. This element may need to be included in narrative because of the potential for modifying information. Annotations SHOULD NOT be used to communicate "modifying" information that could be computable. (This is a SHOULD because enforcing user behavior is nearly impossible). 
 
 | |
| patientInstruction | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.patientInstruction Patient or consumer-oriented instructionsDefinition Instructions in terms that are understood by the patient or consumer. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| relevantHistory | I | 0..* | Reference(UK Core Provenance) | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory Request provenanceDefinition Key events in the history of the request. This might not include provenances for all versions of the request – only those deemed “relevant” or important. This SHALL NOT include the Provenance associated with this current version of the resource. (If that provenance is deemed to be a “relevant” change, it will need to be added as part of a later update. Until then, it can be queried directly as the Provenance that points to this version using _revinclude All Provenances should have some historical version of this Request as their subject. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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Hybrid View
| ServiceRequest | I | ServiceRequest | There are no (further) constraints on this elementElement Id ServiceRequest A request for a service to be performedAlternate names diagnostic request, referral, referral request, transfer of care requestDefinition A record of a request for service such as diagnostic investigations, treatments, or operations to be performed. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id ServiceRequest.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| sourceOfServiceRequest | I | 0..1 | Extension(CodeableConcept) | There are no (further) constraints on this elementElement Id ServiceRequest.extension:sourceOfServiceRequest This represents the source of referralAlternate names extensions, user contentDefinition This represents the source of referral. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-SourceOfServiceRequestConstraints 
 
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| identifier | Σ | 0..* | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.identifier Identifiers assigned to this orderDefinition Identifiers assigned to this order instance by the orderer and/or the receiver and/or order fulfiller. The identifier.type element is used to distinguish between the identifiers assigned by the orderer (known as the 'Placer' in HL7 v2) and the producer of the observations in response to the order (known as the 'Filler' in HL7 v2). For further discussion and examples see the resource notes section below. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| instantiatesCanonical | Σ | 0..* | canonical(ActivityDefinition | PlanDefinition) | There are no (further) constraints on this elementElement Id ServiceRequest.instantiatesCanonical Instantiates FHIR protocol or definitionDefinition The URL pointing to a FHIR-defined protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest. Note: This is a business identifier, not a resource identifier (see discussion). It is best practice for the identifier to only appear on a single resource instance, however business practices may occasionally dictate that multiple resource instances with the same identifier can exist - possibly even with different resource types. For example, multiple Patient and a Person resource instance might share the same social insurance number. canonical(ActivityDefinition | PlanDefinition)Constraints 
 
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| instantiatesUri | Σ | 0..* | uri | There are no (further) constraints on this elementElement Id ServiceRequest.instantiatesUri Instantiates external protocol or definitionDefinition The URL pointing to an externally maintained protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest. This might be an HTML page, PDF, etc. or could just be a non-resolvable URI identifier. 
 
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| basedOn | Σ I | 0..* | Reference(UK Core CarePlan | UK Core MedicationRequest | UK Core ServiceRequest) | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn What request fulfillsAlternate names fulfillsDefinition Plan/proposal/order fulfilled by this request. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core CarePlan | UK Core MedicationRequest | UK Core ServiceRequest)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| replaces | Σ I | 0..* | Reference(UK Core ServiceRequest) | There are no (further) constraints on this elementElement Id ServiceRequest.replaces What request replacesAlternate names supersedes, prior, renewed orderDefinition The request takes the place of the referenced completed or terminated request(s). References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core ServiceRequest)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| requisition | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.requisition Composite Request IDAlternate names grouperId, groupIdentifierDefinition A shared identifier common to all service requests that were authorized more or less simultaneously by a single author, representing the composite or group identifier. Some business processes need to know if multiple items were ordered as part of the same "requisition" for billing or other purposes. Requests are linked either by a "basedOn" relationship (i.e. one request is fulfilling another) or by having a common requisition. Requests that are part of the same requisition are generally treated independently from the perspective of changing their state or maintaining them after initial creation. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| status | Σ ?! | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.status draft | active | on-hold | revoked | completed | entered-in-error | unknownDefinition The status of the order. The status is generally fully in the control of the requester - they determine whether the order is draft or active and, after it has been activated, competed, cancelled or suspended. States relating to the activities of the performer are reflected on either the corresponding event (see Event Pattern for general discussion) or using the Task resource. The status of a service order.RequestStatus (required)Constraints 
 
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| intent | Σ ?! | 1..1 | codeBindingFixed Value | Element Id ServiceRequest.intent proposal | plan | directive | order | original-order | reflex-order | filler-order | instance-order | optionDefinition Whether the request is a proposal, plan, an original order or a reflex order. This element is labeled as a modifier because the intent alters when and how the resource is actually applicable. The kind of service request.RequestIntent (required)Constraints 
 plan 
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| category | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.category Classification of serviceDefinition A code that classifies the service for searching, sorting and display purposes (e.g. "Surgical Procedure"). Used for filtering what service request are retrieved and displayed. There may be multiple axis of categorization depending on the context or use case for retrieving or displaying the resource. The level of granularity is defined by the category concepts in the value set. Classification of the requested service.ServiceRequestCategoryCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id ServiceRequest.category.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. 
 https://fhir.nhs.uk/CodeSystem/message-category-servicerequest 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | codeFixed Value | Element Id ServiceRequest.category.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 referral 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| priority | Σ | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.priority routine | urgent | asap | statDefinition Indicates how quickly the ServiceRequest should be addressed with respect to other requests. Note that FHIR strings SHALL NOT exceed 1MB in size Identifies the level of importance to be assigned to actioning the request.RequestPriority (required)Constraints 
 
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| doNotPerform | Σ ?! | 0..1 | boolean | There are no (further) constraints on this elementElement Id ServiceRequest.doNotPerform True if service/procedure should not be performedDefinition Set this to true if the record is saying that the service/procedure should NOT be performed. Used for do not ambulate, do not elevate head of bed, do not flush NG tube, do not take blood pressure on a certain arm, etc. In general, only the code and timeframe will be present, though occasional additional qualifiers such as body site or even performer could be included to narrow the scope of the prohibition. If the ServiceRequest.code and ServiceRequest.doNotPerform both contain negation, that will reinforce prohibition and should not have a double negative interpretation. 
 
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| code | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.code What is being requested/orderedAlternate names service requestedDefinition A code that identifies a particular service (i.e., procedure, diagnostic investigation, or panel of investigations) that have been requested. Many laboratory and radiology procedure codes embed the specimen/organ system in the test order name, for example, serum or serum/plasma glucose, or a chest x-ray. The specimen might not be recorded separately from the test code. A set of codes that define a procedure or a procedure with explicit context. Selected from the SNOMED CT UK coding system.UKCoreProcedureCode (preferred)Constraints 
 
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| orderDetail | Σ I | 0..* | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.orderDetail Additional order informationAlternate names detailed instructionsDefinition Additional details and instructions about the how the services are to be delivered. For example, and order for a urinary catheter may have an order detail for an external or indwelling catheter, or an order for a bandage may require additional instructions specifying how the bandage should be applied. For information from the medical record intended to support the delivery of the requested services, use the  Codified order entry details which are based on order context.ServiceRequestOrderDetailsCodes (example)Constraints 
 
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| quantity[x] | Σ | 0..1 | There are no (further) constraints on this elementElement Id ServiceRequest.quantity[x] Service amountDefinition An amount of service being requested which can be a quantity ( for example $1,500 home modification), a ratio ( for example, 20 half day visits per month), or a range (2.0 to 1.8 Gy per fraction). When ordering a service the number of service items may need to be specified separately from the the service item. 
 
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| quantityQuantity | Quantity | There are no (further) constraints on this elementData Type | ||
| quantityRatio | Ratio | There are no (further) constraints on this elementData Type | ||
| quantityRange | Range | There are no (further) constraints on this elementData Type | ||
| subject | Σ I | 1..1 | Reference(UK Core Patient) | Element Id ServiceRequest.subject Individual or Entity the service is ordered forDefinition On whom or what the service is to be performed. This is usually a human patient, but can also be requested on animals, groups of humans or animals, devices such as dialysis machines, or even locations (typically for environmental scans). References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| encounter | Σ I | 0..1 | Reference(UK Core Encounter) | Element Id ServiceRequest.encounter Encounter in which the request was createdAlternate names contextDefinition An encounter that provides additional information about the healthcare context in which this request is made. Encounter context 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| occurrence[x] | Σ | 0..1 | Element Id ServiceRequest.occurrence[x] When service should occurAlternate names scheduleDefinition The date/time at which the requested service should occur. Validation Breach Time/Call back breach time 
 
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| occurrencePeriod | Period | Data Type | ||
| asNeeded[x] | Σ | 0..1 | There are no (further) constraints on this elementElement Id ServiceRequest.asNeeded[x] Preconditions for serviceDefinition If a CodeableConcept is present, it indicates the pre-condition for performing the service. For example "pain", "on flare-up", etc. A coded concept identifying the pre-condition that should hold prior to performing a procedure. For example "pain", "on flare-up", etc.SNOMEDCTMedicationAsNeededReasonCodes (example)Constraints 
 
 | |
| asNeededBoolean | boolean | There are no (further) constraints on this elementData Type | ||
| asNeededCodeableConcept | CodeableConcept | There are no (further) constraints on this elementData Type | ||
| authoredOn | Σ | 1..1 | dateTime | Element Id ServiceRequest.authoredOn Date request signedAlternate names orderedOnDefinition When the request transitioned to being actionable. ReferralDateTime 
 
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| requester | Σ I | 0..1 | Reference(UK Core Device | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson) | Element Id ServiceRequest.requester Who/what is requesting serviceAlternate names author, ordererDefinition The individual who initiated the request and has responsibility for its activation. Participant Reference(UK Core Device | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson)Constraints 
 
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| reference | Σ I | 0..1 | string | Element Id ServiceRequest.requester.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Organisation 
 
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| type | Σ | 0..1 | uriBinding | Element Id ServiceRequest.requester.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Service Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requester.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| performerType | Σ | 0..1 | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.performerType Performer roleAlternate names specialtyDefinition Desired type of performer for doing the requested service. This is a role, not a participation type. In other words, does not describe the task but describes the capacity. For example, “compounding pharmacy”, “psychiatrist” or “internal referral”. Indicates specific responsibility of an individual within the care team, such as "Primary physician", "Team coordinator", "Caregiver", etc.ParticipantRoles (example)Constraints 
 
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| performer | Σ I | 0..* | Reference(UK Core CareTeam | UK Core Device | UK Core HealthcareService | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson) | Element Id ServiceRequest.performer Requested performerAlternate names request recipientDefinition The desired performer for doing the requested service. For example, the surgeon, dermatopathologist, endoscopist, etc. Referral To Reference(UK Core CareTeam | UK Core Device | UK Core HealthcareService | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| locationCode | Σ | 0..* | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.locationCode Requested locationDefinition The preferred location(s) where the procedure should actually happen in coded or free text form. E.g. at home or nursing day care center. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. A location type where services are delivered.v3.ServiceDeliveryLocationRoleType (example)Constraints 
 
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| locationReference | Σ I | 0..* | Reference(UK Core Location) | Element Id ServiceRequest.locationReference Requested locationDefinition A reference to the the preferred location(s) where the procedure should actually happen. E.g. at home or nursing day care center. Incident location 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reasonCode | Σ | 0..* | CodeableConceptBinding | Element Id ServiceRequest.reasonCode Explanation/Justification for procedure or serviceDefinition An explanation or justification for why this service is being requested in coded or textual form.   This is often for billing purposes.  May relate to the resources referred to in  Reason for referral/Next activity/Clinical Urgency of Referral A set of codes that define a reason for a service request.UKCoreServiceRequestReasonCode (extensible)Constraints 
 
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| coding | Σ | 0..* | Coding | Element Id ServiceRequest.reasonCode.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Proprietary Triage Outcome code system 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonCode.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| reasonReference | Σ I | 0..* | Reference(UK Core Condition | UK Core DiagnosticReport | UK Core DocumentReference | UK Core Observation) | Element Id ServiceRequest.reasonReference Explanation/Justification for service or serviceDefinition Indicates another resource that provides a justification for why this service is being requested.   May relate to the resources referred to in  Chief concern Reference(UK Core Condition | UK Core DiagnosticReport | UK Core DocumentReference | UK Core Observation)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| insurance | I | 0..* | Reference(Coverage | ClaimResponse) | There are no (further) constraints on this elementElement Id ServiceRequest.insurance Associated insurance coverageDefinition Insurance plans, coverage extensions, pre-authorizations and/or pre-determinations that may be needed for delivering the requested service. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(Coverage | ClaimResponse)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| supportingInfo | I | 0..* | Reference(Resource) | Element Id ServiceRequest.supportingInfo Additional clinical informationAlternate names Ask at order entry question, AOEDefinition Additional clinical information about the patient or specimen that may influence the services or their interpretations. This information includes diagnosis, clinical findings and other observations. In laboratory ordering these are typically referred to as "ask at order entry questions (AOEs)". This includes observations explicitly requested by the producer (filler) to provide context or supporting information needed to complete the order. For example, reporting the amount of inspired oxygen for blood gas measurements. Rejected Services/patient choice (QuestionnaireResponse), Secondary concern (Condition) 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| specimen | Σ I | 0..* | Reference(UK Core Specimen) | There are no (further) constraints on this elementElement Id ServiceRequest.specimen Procedure SamplesDefinition One or more specimens that the laboratory procedure will use. Many diagnostic procedures need a specimen, but the request itself is not actually about the specimen. This element is for when the diagnostic is requested on already existing specimens and the request points to the specimen it applies to. Conversely, if the request is entered first with an unknown specimen, then the Specimen resource points to the ServiceRequest. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| bodySite | Σ | 0..* | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.bodySite Location on BodyAlternate names locationDefinition Anatomic location where the procedure should be performed. This is the target site. Knowing where the procedure is performed is important for tracking if multiple sites are possible. Only used if not implicit in the code found in ServiceRequest.code. If the use case requires BodySite to be handled as a separate resource instead of an inline coded element (e.g. to identify and track separately) then use the standard extension procedure-targetBodyStructure. A set of codes that define an anatomical or acquired body structure site. Selected from the SNOMED CT UK coding system.UKCoreBodySite (extensible)Constraints 
 
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| note | 0..* | Annotation | There are no (further) constraints on this elementElement Id ServiceRequest.note CommentsDefinition Any other notes and comments made about the service request. For example, internal billing notes. For systems that do not have structured annotations, they can simply communicate a single annotation with no author or time. This element may need to be included in narrative because of the potential for modifying information. Annotations SHOULD NOT be used to communicate "modifying" information that could be computable. (This is a SHOULD because enforcing user behavior is nearly impossible). 
 
 | |
| patientInstruction | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.patientInstruction Patient or consumer-oriented instructionsDefinition Instructions in terms that are understood by the patient or consumer. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| relevantHistory | I | 0..* | Reference(UK Core Provenance) | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory Request provenanceDefinition Key events in the history of the request. This might not include provenances for all versions of the request – only those deemed “relevant” or important. This SHALL NOT include the Provenance associated with this current version of the resource. (If that provenance is deemed to be a “relevant” change, it will need to be added as part of a later update. Until then, it can be queried directly as the Provenance that points to this version using _revinclude All Provenances should have some historical version of this Request as their subject. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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Snapshot View
| ServiceRequest | I | ServiceRequest | There are no (further) constraints on this elementElement Id ServiceRequest A request for a service to be performedAlternate names diagnostic request, referral, referral request, transfer of care requestDefinition A record of a request for service such as diagnostic investigations, treatments, or operations to be performed. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id ServiceRequest.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| sourceOfServiceRequest | I | 0..1 | Extension(CodeableConcept) | There are no (further) constraints on this elementElement Id ServiceRequest.extension:sourceOfServiceRequest This represents the source of referralAlternate names extensions, user contentDefinition This represents the source of referral. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-SourceOfServiceRequestConstraints 
 
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| identifier | Σ | 0..* | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.identifier Identifiers assigned to this orderDefinition Identifiers assigned to this order instance by the orderer and/or the receiver and/or order fulfiller. The identifier.type element is used to distinguish between the identifiers assigned by the orderer (known as the 'Placer' in HL7 v2) and the producer of the observations in response to the order (known as the 'Filler' in HL7 v2). For further discussion and examples see the resource notes section below. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| instantiatesCanonical | Σ | 0..* | canonical(ActivityDefinition | PlanDefinition) | There are no (further) constraints on this elementElement Id ServiceRequest.instantiatesCanonical Instantiates FHIR protocol or definitionDefinition The URL pointing to a FHIR-defined protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest. Note: This is a business identifier, not a resource identifier (see discussion). It is best practice for the identifier to only appear on a single resource instance, however business practices may occasionally dictate that multiple resource instances with the same identifier can exist - possibly even with different resource types. For example, multiple Patient and a Person resource instance might share the same social insurance number. canonical(ActivityDefinition | PlanDefinition)Constraints 
 
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| instantiatesUri | Σ | 0..* | uri | There are no (further) constraints on this elementElement Id ServiceRequest.instantiatesUri Instantiates external protocol or definitionDefinition The URL pointing to an externally maintained protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest. This might be an HTML page, PDF, etc. or could just be a non-resolvable URI identifier. 
 
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| basedOn | Σ I | 0..* | Reference(UK Core CarePlan | UK Core MedicationRequest | UK Core ServiceRequest) | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn What request fulfillsAlternate names fulfillsDefinition Plan/proposal/order fulfilled by this request. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core CarePlan | UK Core MedicationRequest | UK Core ServiceRequest)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| replaces | Σ I | 0..* | Reference(UK Core ServiceRequest) | There are no (further) constraints on this elementElement Id ServiceRequest.replaces What request replacesAlternate names supersedes, prior, renewed orderDefinition The request takes the place of the referenced completed or terminated request(s). References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core ServiceRequest)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| requisition | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.requisition Composite Request IDAlternate names grouperId, groupIdentifierDefinition A shared identifier common to all service requests that were authorized more or less simultaneously by a single author, representing the composite or group identifier. Some business processes need to know if multiple items were ordered as part of the same "requisition" for billing or other purposes. Requests are linked either by a "basedOn" relationship (i.e. one request is fulfilling another) or by having a common requisition. Requests that are part of the same requisition are generally treated independently from the perspective of changing their state or maintaining them after initial creation. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| status | Σ ?! | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.status draft | active | on-hold | revoked | completed | entered-in-error | unknownDefinition The status of the order. The status is generally fully in the control of the requester - they determine whether the order is draft or active and, after it has been activated, competed, cancelled or suspended. States relating to the activities of the performer are reflected on either the corresponding event (see Event Pattern for general discussion) or using the Task resource. The status of a service order.RequestStatus (required)Constraints 
 
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| intent | Σ ?! | 1..1 | codeBindingFixed Value | Element Id ServiceRequest.intent proposal | plan | directive | order | original-order | reflex-order | filler-order | instance-order | optionDefinition Whether the request is a proposal, plan, an original order or a reflex order. This element is labeled as a modifier because the intent alters when and how the resource is actually applicable. The kind of service request.RequestIntent (required)Constraints 
 plan 
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| category | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.category Classification of serviceDefinition A code that classifies the service for searching, sorting and display purposes (e.g. "Surgical Procedure"). Used for filtering what service request are retrieved and displayed. There may be multiple axis of categorization depending on the context or use case for retrieving or displaying the resource. The level of granularity is defined by the category concepts in the value set. Classification of the requested service.ServiceRequestCategoryCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id ServiceRequest.category.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. 
 https://fhir.nhs.uk/CodeSystem/message-category-servicerequest 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | codeFixed Value | Element Id ServiceRequest.category.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 referral 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| priority | Σ | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.priority routine | urgent | asap | statDefinition Indicates how quickly the ServiceRequest should be addressed with respect to other requests. Note that FHIR strings SHALL NOT exceed 1MB in size Identifies the level of importance to be assigned to actioning the request.RequestPriority (required)Constraints 
 
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| doNotPerform | Σ ?! | 0..1 | boolean | There are no (further) constraints on this elementElement Id ServiceRequest.doNotPerform True if service/procedure should not be performedDefinition Set this to true if the record is saying that the service/procedure should NOT be performed. Used for do not ambulate, do not elevate head of bed, do not flush NG tube, do not take blood pressure on a certain arm, etc. In general, only the code and timeframe will be present, though occasional additional qualifiers such as body site or even performer could be included to narrow the scope of the prohibition. If the ServiceRequest.code and ServiceRequest.doNotPerform both contain negation, that will reinforce prohibition and should not have a double negative interpretation. 
 
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| code | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.code What is being requested/orderedAlternate names service requestedDefinition A code that identifies a particular service (i.e., procedure, diagnostic investigation, or panel of investigations) that have been requested. Many laboratory and radiology procedure codes embed the specimen/organ system in the test order name, for example, serum or serum/plasma glucose, or a chest x-ray. The specimen might not be recorded separately from the test code. A set of codes that define a procedure or a procedure with explicit context. Selected from the SNOMED CT UK coding system.UKCoreProcedureCode (preferred)Constraints 
 
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| orderDetail | Σ I | 0..* | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.orderDetail Additional order informationAlternate names detailed instructionsDefinition Additional details and instructions about the how the services are to be delivered. For example, and order for a urinary catheter may have an order detail for an external or indwelling catheter, or an order for a bandage may require additional instructions specifying how the bandage should be applied. For information from the medical record intended to support the delivery of the requested services, use the  Codified order entry details which are based on order context.ServiceRequestOrderDetailsCodes (example)Constraints 
 
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| quantity[x] | Σ | 0..1 | There are no (further) constraints on this elementElement Id ServiceRequest.quantity[x] Service amountDefinition An amount of service being requested which can be a quantity ( for example $1,500 home modification), a ratio ( for example, 20 half day visits per month), or a range (2.0 to 1.8 Gy per fraction). When ordering a service the number of service items may need to be specified separately from the the service item. 
 
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| quantityQuantity | Quantity | There are no (further) constraints on this elementData Type | ||
| quantityRatio | Ratio | There are no (further) constraints on this elementData Type | ||
| quantityRange | Range | There are no (further) constraints on this elementData Type | ||
| subject | Σ I | 1..1 | Reference(UK Core Patient) | Element Id ServiceRequest.subject Individual or Entity the service is ordered forDefinition On whom or what the service is to be performed. This is usually a human patient, but can also be requested on animals, groups of humans or animals, devices such as dialysis machines, or even locations (typically for environmental scans). References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| encounter | Σ I | 0..1 | Reference(UK Core Encounter) | Element Id ServiceRequest.encounter Encounter in which the request was createdAlternate names contextDefinition An encounter that provides additional information about the healthcare context in which this request is made. Encounter context 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| occurrence[x] | Σ | 0..1 | Element Id ServiceRequest.occurrence[x] When service should occurAlternate names scheduleDefinition The date/time at which the requested service should occur. Validation Breach Time/Call back breach time 
 
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| occurrencePeriod | Period | Data Type | ||
| asNeeded[x] | Σ | 0..1 | There are no (further) constraints on this elementElement Id ServiceRequest.asNeeded[x] Preconditions for serviceDefinition If a CodeableConcept is present, it indicates the pre-condition for performing the service. For example "pain", "on flare-up", etc. A coded concept identifying the pre-condition that should hold prior to performing a procedure. For example "pain", "on flare-up", etc.SNOMEDCTMedicationAsNeededReasonCodes (example)Constraints 
 
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| asNeededBoolean | boolean | There are no (further) constraints on this elementData Type | ||
| asNeededCodeableConcept | CodeableConcept | There are no (further) constraints on this elementData Type | ||
| authoredOn | Σ | 1..1 | dateTime | Element Id ServiceRequest.authoredOn Date request signedAlternate names orderedOnDefinition When the request transitioned to being actionable. ReferralDateTime 
 
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| requester | Σ I | 0..1 | Reference(UK Core Device | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson) | Element Id ServiceRequest.requester Who/what is requesting serviceAlternate names author, ordererDefinition The individual who initiated the request and has responsibility for its activation. Participant Reference(UK Core Device | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson)Constraints 
 
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| reference | Σ I | 0..1 | string | Element Id ServiceRequest.requester.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Organisation 
 
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| type | Σ | 0..1 | uriBinding | Element Id ServiceRequest.requester.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Service Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requester.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| performerType | Σ | 0..1 | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.performerType Performer roleAlternate names specialtyDefinition Desired type of performer for doing the requested service. This is a role, not a participation type. In other words, does not describe the task but describes the capacity. For example, “compounding pharmacy”, “psychiatrist” or “internal referral”. Indicates specific responsibility of an individual within the care team, such as "Primary physician", "Team coordinator", "Caregiver", etc.ParticipantRoles (example)Constraints 
 
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| performer | Σ I | 0..* | Reference(UK Core CareTeam | UK Core Device | UK Core HealthcareService | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson) | Element Id ServiceRequest.performer Requested performerAlternate names request recipientDefinition The desired performer for doing the requested service. For example, the surgeon, dermatopathologist, endoscopist, etc. Referral To Reference(UK Core CareTeam | UK Core Device | UK Core HealthcareService | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| locationCode | Σ | 0..* | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.locationCode Requested locationDefinition The preferred location(s) where the procedure should actually happen in coded or free text form. E.g. at home or nursing day care center. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. A location type where services are delivered.v3.ServiceDeliveryLocationRoleType (example)Constraints 
 
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| locationReference | Σ I | 0..* | Reference(UK Core Location) | Element Id ServiceRequest.locationReference Requested locationDefinition A reference to the the preferred location(s) where the procedure should actually happen. E.g. at home or nursing day care center. Incident location 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reasonCode | Σ | 0..* | CodeableConceptBinding | Element Id ServiceRequest.reasonCode Explanation/Justification for procedure or serviceDefinition An explanation or justification for why this service is being requested in coded or textual form.   This is often for billing purposes.  May relate to the resources referred to in  Reason for referral/Next activity/Clinical Urgency of Referral A set of codes that define a reason for a service request.UKCoreServiceRequestReasonCode (extensible)Constraints 
 
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| coding | Σ | 0..* | Coding | Element Id ServiceRequest.reasonCode.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Proprietary Triage Outcome code system 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonCode.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| reasonReference | Σ I | 0..* | Reference(UK Core Condition | UK Core DiagnosticReport | UK Core DocumentReference | UK Core Observation) | Element Id ServiceRequest.reasonReference Explanation/Justification for service or serviceDefinition Indicates another resource that provides a justification for why this service is being requested.   May relate to the resources referred to in  Chief concern Reference(UK Core Condition | UK Core DiagnosticReport | UK Core DocumentReference | UK Core Observation)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| insurance | I | 0..* | Reference(Coverage | ClaimResponse) | There are no (further) constraints on this elementElement Id ServiceRequest.insurance Associated insurance coverageDefinition Insurance plans, coverage extensions, pre-authorizations and/or pre-determinations that may be needed for delivering the requested service. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(Coverage | ClaimResponse)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| supportingInfo | I | 0..* | Reference(Resource) | Element Id ServiceRequest.supportingInfo Additional clinical informationAlternate names Ask at order entry question, AOEDefinition Additional clinical information about the patient or specimen that may influence the services or their interpretations. This information includes diagnosis, clinical findings and other observations. In laboratory ordering these are typically referred to as "ask at order entry questions (AOEs)". This includes observations explicitly requested by the producer (filler) to provide context or supporting information needed to complete the order. For example, reporting the amount of inspired oxygen for blood gas measurements. Rejected Services/patient choice (QuestionnaireResponse), Secondary concern (Condition) 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| specimen | Σ I | 0..* | Reference(UK Core Specimen) | There are no (further) constraints on this elementElement Id ServiceRequest.specimen Procedure SamplesDefinition One or more specimens that the laboratory procedure will use. Many diagnostic procedures need a specimen, but the request itself is not actually about the specimen. This element is for when the diagnostic is requested on already existing specimens and the request points to the specimen it applies to. Conversely, if the request is entered first with an unknown specimen, then the Specimen resource points to the ServiceRequest. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| bodySite | Σ | 0..* | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.bodySite Location on BodyAlternate names locationDefinition Anatomic location where the procedure should be performed. This is the target site. Knowing where the procedure is performed is important for tracking if multiple sites are possible. Only used if not implicit in the code found in ServiceRequest.code. If the use case requires BodySite to be handled as a separate resource instead of an inline coded element (e.g. to identify and track separately) then use the standard extension procedure-targetBodyStructure. A set of codes that define an anatomical or acquired body structure site. Selected from the SNOMED CT UK coding system.UKCoreBodySite (extensible)Constraints 
 
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| note | 0..* | Annotation | There are no (further) constraints on this elementElement Id ServiceRequest.note CommentsDefinition Any other notes and comments made about the service request. For example, internal billing notes. For systems that do not have structured annotations, they can simply communicate a single annotation with no author or time. This element may need to be included in narrative because of the potential for modifying information. Annotations SHOULD NOT be used to communicate "modifying" information that could be computable. (This is a SHOULD because enforcing user behavior is nearly impossible). 
 
 | |
| patientInstruction | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.patientInstruction Patient or consumer-oriented instructionsDefinition Instructions in terms that are understood by the patient or consumer. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| relevantHistory | I | 0..* | Reference(UK Core Provenance) | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory Request provenanceDefinition Key events in the history of the request. This might not include provenances for all versions of the request – only those deemed “relevant” or important. This SHALL NOT include the Provenance associated with this current version of the resource. (If that provenance is deemed to be a “relevant” change, it will need to be added as part of a later update. Until then, it can be queried directly as the Provenance that points to this version using _revinclude All Provenances should have some historical version of this Request as their subject. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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Examples
BARS ServiceRequest-Request Validation
Defines the constraints and extensions on the UKCore-Bundle FHIR Profile
Based on: UKCore.Release1@1.0.1/package/UKCore-Bundle
Differential View
| ServiceRequest | I | ServiceRequest | There are no (further) constraints on this elementElement Id ServiceRequest A request for a service to be performedAlternate names diagnostic request, referral, referral request, transfer of care requestDefinition A record of a request for service such as diagnostic investigations, treatments, or operations to be performed. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id ServiceRequest.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| sourceOfServiceRequest | I | 0..1 | Extension(CodeableConcept) | There are no (further) constraints on this elementElement Id ServiceRequest.extension:sourceOfServiceRequest This represents the source of referralAlternate names extensions, user contentDefinition This represents the source of referral. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-SourceOfServiceRequestConstraints 
 
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| identifier | Σ | 0..* | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.identifier Identifiers assigned to this orderDefinition Identifiers assigned to this order instance by the orderer and/or the receiver and/or order fulfiller. The identifier.type element is used to distinguish between the identifiers assigned by the orderer (known as the 'Placer' in HL7 v2) and the producer of the observations in response to the order (known as the 'Filler' in HL7 v2). For further discussion and examples see the resource notes section below. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| instantiatesCanonical | Σ | 0..* | canonical(ActivityDefinition | PlanDefinition) | There are no (further) constraints on this elementElement Id ServiceRequest.instantiatesCanonical Instantiates FHIR protocol or definitionDefinition The URL pointing to a FHIR-defined protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest. Note: This is a business identifier, not a resource identifier (see discussion). It is best practice for the identifier to only appear on a single resource instance, however business practices may occasionally dictate that multiple resource instances with the same identifier can exist - possibly even with different resource types. For example, multiple Patient and a Person resource instance might share the same social insurance number. canonical(ActivityDefinition | PlanDefinition)Constraints 
 
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| instantiatesUri | Σ | 0..* | uri | There are no (further) constraints on this elementElement Id ServiceRequest.instantiatesUri Instantiates external protocol or definitionDefinition The URL pointing to an externally maintained protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest. This might be an HTML page, PDF, etc. or could just be a non-resolvable URI identifier. 
 
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| basedOn | Σ I | 0..* | Reference(UK Core CarePlan | UK Core MedicationRequest | UK Core ServiceRequest) | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn What request fulfillsAlternate names fulfillsDefinition Plan/proposal/order fulfilled by this request. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core CarePlan | UK Core MedicationRequest | UK Core ServiceRequest)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| replaces | Σ I | 0..* | Reference(UK Core ServiceRequest) | There are no (further) constraints on this elementElement Id ServiceRequest.replaces What request replacesAlternate names supersedes, prior, renewed orderDefinition The request takes the place of the referenced completed or terminated request(s). References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core ServiceRequest)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| requisition | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.requisition Composite Request IDAlternate names grouperId, groupIdentifierDefinition A shared identifier common to all service requests that were authorized more or less simultaneously by a single author, representing the composite or group identifier. Some business processes need to know if multiple items were ordered as part of the same "requisition" for billing or other purposes. Requests are linked either by a "basedOn" relationship (i.e. one request is fulfilling another) or by having a common requisition. Requests that are part of the same requisition are generally treated independently from the perspective of changing their state or maintaining them after initial creation. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| status | Σ ?! | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.status draft | active | on-hold | revoked | completed | entered-in-error | unknownDefinition The status of the order. The status is generally fully in the control of the requester - they determine whether the order is draft or active and, after it has been activated, competed, cancelled or suspended. States relating to the activities of the performer are reflected on either the corresponding event (see Event Pattern for general discussion) or using the Task resource. The status of a service order.RequestStatus (required)Constraints 
 
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| intent | Σ ?! | 1..1 | codeBindingFixed Value | Element Id ServiceRequest.intent proposal | plan | directive | order | original-order | reflex-order | filler-order | instance-order | optionDefinition Whether the request is a proposal, plan, an original order or a reflex order. This element is labeled as a modifier because the intent alters when and how the resource is actually applicable. The kind of service request.RequestIntent (required)Constraints 
 plan 
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| category | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.category Classification of serviceDefinition A code that classifies the service for searching, sorting and display purposes (e.g. "Surgical Procedure"). Used for filtering what service request are retrieved and displayed. There may be multiple axis of categorization depending on the context or use case for retrieving or displaying the resource. The level of granularity is defined by the category concepts in the value set. Classification of the requested service.ServiceRequestCategoryCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id ServiceRequest.category.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. 
 https://fhir.nhs.uk/CodeSystem/message-category-servicerequest 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | codeFixed Value | Element Id ServiceRequest.category.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 validation 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| priority | Σ | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.priority routine | urgent | asap | statDefinition Indicates how quickly the ServiceRequest should be addressed with respect to other requests. Note that FHIR strings SHALL NOT exceed 1MB in size Identifies the level of importance to be assigned to actioning the request.RequestPriority (required)Constraints 
 
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| doNotPerform | Σ ?! | 0..1 | boolean | There are no (further) constraints on this elementElement Id ServiceRequest.doNotPerform True if service/procedure should not be performedDefinition Set this to true if the record is saying that the service/procedure should NOT be performed. Used for do not ambulate, do not elevate head of bed, do not flush NG tube, do not take blood pressure on a certain arm, etc. In general, only the code and timeframe will be present, though occasional additional qualifiers such as body site or even performer could be included to narrow the scope of the prohibition. If the ServiceRequest.code and ServiceRequest.doNotPerform both contain negation, that will reinforce prohibition and should not have a double negative interpretation. 
 
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| code | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.code What is being requested/orderedAlternate names service requestedDefinition A code that identifies a particular service (i.e., procedure, diagnostic investigation, or panel of investigations) that have been requested. Many laboratory and radiology procedure codes embed the specimen/organ system in the test order name, for example, serum or serum/plasma glucose, or a chest x-ray. The specimen might not be recorded separately from the test code. A set of codes that define a procedure or a procedure with explicit context. Selected from the SNOMED CT UK coding system.UKCoreProcedureCode (preferred)Constraints 
 
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| orderDetail | Σ I | 0..* | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.orderDetail Additional order informationAlternate names detailed instructionsDefinition Additional details and instructions about the how the services are to be delivered. For example, and order for a urinary catheter may have an order detail for an external or indwelling catheter, or an order for a bandage may require additional instructions specifying how the bandage should be applied. For information from the medical record intended to support the delivery of the requested services, use the  Codified order entry details which are based on order context.ServiceRequestOrderDetailsCodes (example)Constraints 
 
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| quantity[x] | Σ | 0..1 | There are no (further) constraints on this elementElement Id ServiceRequest.quantity[x] Service amountDefinition An amount of service being requested which can be a quantity ( for example $1,500 home modification), a ratio ( for example, 20 half day visits per month), or a range (2.0 to 1.8 Gy per fraction). When ordering a service the number of service items may need to be specified separately from the the service item. 
 
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| quantityQuantity | Quantity | There are no (further) constraints on this elementData Type | ||
| quantityRatio | Ratio | There are no (further) constraints on this elementData Type | ||
| quantityRange | Range | There are no (further) constraints on this elementData Type | ||
| subject | Σ I | 1..1 | Reference(UK Core Patient) | Element Id ServiceRequest.subject Individual or Entity the service is ordered forDefinition On whom or what the service is to be performed. This is usually a human patient, but can also be requested on animals, groups of humans or animals, devices such as dialysis machines, or even locations (typically for environmental scans). References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| encounter | Σ I | 0..1 | Reference(UK Core Encounter) | Element Id ServiceRequest.encounter Encounter in which the request was createdAlternate names contextDefinition An encounter that provides additional information about the healthcare context in which this request is made. Encounter context 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| occurrence[x] | Σ | 0..1 | Element Id ServiceRequest.occurrence[x] When service should occurAlternate names scheduleDefinition The date/time at which the requested service should occur. Validation Breach Time/Call back breach time 
 
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| occurrencePeriod | Period | Data Type | ||
| start | Σ I | 1..1 | dateTime | There are no (further) constraints on this elementElement Id ServiceRequest.occurrence[x].start Starting time with inclusive boundaryDefinition The start of the period. The boundary is inclusive. If the low element is missing, the meaning is that the low boundary is not known. 
 
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| end | Σ I | 1..1 | dateTime | There are no (further) constraints on this elementElement Id ServiceRequest.occurrence[x].end End time with inclusive boundary, if not ongoingDefinition The end of the period. If the end of the period is missing, it means no end was known or planned at the time the instance was created. The start may be in the past, and the end date in the future, which means that period is expected/planned to end at that time. The high value includes any matching date/time. i.e. 2012-02-03T10:00:00 is in a period that has an end value of 2012-02-03. 
 
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| asNeeded[x] | Σ | 0..1 | There are no (further) constraints on this elementElement Id ServiceRequest.asNeeded[x] Preconditions for serviceDefinition If a CodeableConcept is present, it indicates the pre-condition for performing the service. For example "pain", "on flare-up", etc. A coded concept identifying the pre-condition that should hold prior to performing a procedure. For example "pain", "on flare-up", etc.SNOMEDCTMedicationAsNeededReasonCodes (example)Constraints 
 
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| asNeededBoolean | boolean | There are no (further) constraints on this elementData Type | ||
| asNeededCodeableConcept | CodeableConcept | There are no (further) constraints on this elementData Type | ||
| authoredOn | Σ | 0..1 | dateTime | Element Id ServiceRequest.authoredOn Date request signedAlternate names orderedOnDefinition When the request transitioned to being actionable. ReferralDateTime 
 
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| requester | Σ I | 0..1 | Reference(UK Core Device | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson) | Element Id ServiceRequest.requester Who/what is requesting serviceAlternate names author, ordererDefinition The individual who initiated the request and has responsibility for its activation. Participant Reference(UK Core Device | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson)Constraints 
 
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| reference | Σ I | 0..1 | string | Element Id ServiceRequest.requester.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Organisation 
 
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| type | Σ | 0..1 | uriBinding | Element Id ServiceRequest.requester.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Service Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requester.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| performerType | Σ | 0..1 | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.performerType Performer roleAlternate names specialtyDefinition Desired type of performer for doing the requested service. This is a role, not a participation type. In other words, does not describe the task but describes the capacity. For example, “compounding pharmacy”, “psychiatrist” or “internal referral”. Indicates specific responsibility of an individual within the care team, such as "Primary physician", "Team coordinator", "Caregiver", etc.ParticipantRoles (example)Constraints 
 
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| performer | Σ I | 0..* | Reference(UK Core CareTeam | UK Core Device | UK Core HealthcareService | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson) | Element Id ServiceRequest.performer Requested performerAlternate names request recipientDefinition The desired performer for doing the requested service. For example, the surgeon, dermatopathologist, endoscopist, etc. Referral To Reference(UK Core CareTeam | UK Core Device | UK Core HealthcareService | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| locationCode | Σ | 0..* | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.locationCode Requested locationDefinition The preferred location(s) where the procedure should actually happen in coded or free text form. E.g. at home or nursing day care center. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. A location type where services are delivered.v3.ServiceDeliveryLocationRoleType (example)Constraints 
 
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| locationReference | Σ I | 0..* | Reference(UK Core Location) | Element Id ServiceRequest.locationReference Requested locationDefinition A reference to the the preferred location(s) where the procedure should actually happen. E.g. at home or nursing day care center. Incident location 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reasonCode | Σ | 0..* | CodeableConceptBinding | Element Id ServiceRequest.reasonCode Explanation/Justification for procedure or serviceDefinition An explanation or justification for why this service is being requested in coded or textual form.   This is often for billing purposes.  May relate to the resources referred to in  Reason for referral/Next activity/Clinical Urgency of Referral A set of codes that define a reason for a service request.UKCoreServiceRequestReasonCode (extensible)Constraints 
 
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| coding | Σ | 0..* | Coding | Element Id ServiceRequest.reasonCode.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Proprietary Triage Outcome code system 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonCode.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| reasonReference | Σ I | 0..* | Reference(UK Core Condition | UK Core DiagnosticReport | UK Core DocumentReference | UK Core Observation) | Element Id ServiceRequest.reasonReference Explanation/Justification for service or serviceDefinition Indicates another resource that provides a justification for why this service is being requested.   May relate to the resources referred to in  Chief concern Reference(UK Core Condition | UK Core DiagnosticReport | UK Core DocumentReference | UK Core Observation)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| insurance | I | 0..* | Reference(Coverage | ClaimResponse) | There are no (further) constraints on this elementElement Id ServiceRequest.insurance Associated insurance coverageDefinition Insurance plans, coverage extensions, pre-authorizations and/or pre-determinations that may be needed for delivering the requested service. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(Coverage | ClaimResponse)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| supportingInfo | I | 0..* | Reference(Resource) | Element Id ServiceRequest.supportingInfo Additional clinical informationAlternate names Ask at order entry question, AOEDefinition Additional clinical information about the patient or specimen that may influence the services or their interpretations. This information includes diagnosis, clinical findings and other observations. In laboratory ordering these are typically referred to as "ask at order entry questions (AOEs)". This includes observations explicitly requested by the producer (filler) to provide context or supporting information needed to complete the order. For example, reporting the amount of inspired oxygen for blood gas measurements. Rejected Services/patient choice (QuestionnaireResponse), Secondary concern (Condition) 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| specimen | Σ I | 0..* | Reference(UK Core Specimen) | There are no (further) constraints on this elementElement Id ServiceRequest.specimen Procedure SamplesDefinition One or more specimens that the laboratory procedure will use. Many diagnostic procedures need a specimen, but the request itself is not actually about the specimen. This element is for when the diagnostic is requested on already existing specimens and the request points to the specimen it applies to. Conversely, if the request is entered first with an unknown specimen, then the Specimen resource points to the ServiceRequest. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| bodySite | Σ | 0..* | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.bodySite Location on BodyAlternate names locationDefinition Anatomic location where the procedure should be performed. This is the target site. Knowing where the procedure is performed is important for tracking if multiple sites are possible. Only used if not implicit in the code found in ServiceRequest.code. If the use case requires BodySite to be handled as a separate resource instead of an inline coded element (e.g. to identify and track separately) then use the standard extension procedure-targetBodyStructure. A set of codes that define an anatomical or acquired body structure site. Selected from the SNOMED CT UK coding system.UKCoreBodySite (extensible)Constraints 
 
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| note | 0..* | Annotation | There are no (further) constraints on this elementElement Id ServiceRequest.note CommentsDefinition Any other notes and comments made about the service request. For example, internal billing notes. For systems that do not have structured annotations, they can simply communicate a single annotation with no author or time. This element may need to be included in narrative because of the potential for modifying information. Annotations SHOULD NOT be used to communicate "modifying" information that could be computable. (This is a SHOULD because enforcing user behavior is nearly impossible). 
 
 | |
| patientInstruction | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.patientInstruction Patient or consumer-oriented instructionsDefinition Instructions in terms that are understood by the patient or consumer. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| relevantHistory | I | 0..* | Reference(UK Core Provenance) | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory Request provenanceDefinition Key events in the history of the request. This might not include provenances for all versions of the request – only those deemed “relevant” or important. This SHALL NOT include the Provenance associated with this current version of the resource. (If that provenance is deemed to be a “relevant” change, it will need to be added as part of a later update. Until then, it can be queried directly as the Provenance that points to this version using _revinclude All Provenances should have some historical version of this Request as their subject. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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Hybrid View
| ServiceRequest | I | ServiceRequest | There are no (further) constraints on this elementElement Id ServiceRequest A request for a service to be performedAlternate names diagnostic request, referral, referral request, transfer of care requestDefinition A record of a request for service such as diagnostic investigations, treatments, or operations to be performed. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id ServiceRequest.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| sourceOfServiceRequest | I | 0..1 | Extension(CodeableConcept) | There are no (further) constraints on this elementElement Id ServiceRequest.extension:sourceOfServiceRequest This represents the source of referralAlternate names extensions, user contentDefinition This represents the source of referral. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-SourceOfServiceRequestConstraints 
 
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| identifier | Σ | 0..* | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.identifier Identifiers assigned to this orderDefinition Identifiers assigned to this order instance by the orderer and/or the receiver and/or order fulfiller. The identifier.type element is used to distinguish between the identifiers assigned by the orderer (known as the 'Placer' in HL7 v2) and the producer of the observations in response to the order (known as the 'Filler' in HL7 v2). For further discussion and examples see the resource notes section below. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| instantiatesCanonical | Σ | 0..* | canonical(ActivityDefinition | PlanDefinition) | There are no (further) constraints on this elementElement Id ServiceRequest.instantiatesCanonical Instantiates FHIR protocol or definitionDefinition The URL pointing to a FHIR-defined protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest. Note: This is a business identifier, not a resource identifier (see discussion). It is best practice for the identifier to only appear on a single resource instance, however business practices may occasionally dictate that multiple resource instances with the same identifier can exist - possibly even with different resource types. For example, multiple Patient and a Person resource instance might share the same social insurance number. canonical(ActivityDefinition | PlanDefinition)Constraints 
 
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| instantiatesUri | Σ | 0..* | uri | There are no (further) constraints on this elementElement Id ServiceRequest.instantiatesUri Instantiates external protocol or definitionDefinition The URL pointing to an externally maintained protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest. This might be an HTML page, PDF, etc. or could just be a non-resolvable URI identifier. 
 
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| basedOn | Σ I | 0..* | Reference(UK Core CarePlan | UK Core MedicationRequest | UK Core ServiceRequest) | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn What request fulfillsAlternate names fulfillsDefinition Plan/proposal/order fulfilled by this request. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core CarePlan | UK Core MedicationRequest | UK Core ServiceRequest)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| replaces | Σ I | 0..* | Reference(UK Core ServiceRequest) | There are no (further) constraints on this elementElement Id ServiceRequest.replaces What request replacesAlternate names supersedes, prior, renewed orderDefinition The request takes the place of the referenced completed or terminated request(s). References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core ServiceRequest)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| requisition | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.requisition Composite Request IDAlternate names grouperId, groupIdentifierDefinition A shared identifier common to all service requests that were authorized more or less simultaneously by a single author, representing the composite or group identifier. Some business processes need to know if multiple items were ordered as part of the same "requisition" for billing or other purposes. Requests are linked either by a "basedOn" relationship (i.e. one request is fulfilling another) or by having a common requisition. Requests that are part of the same requisition are generally treated independently from the perspective of changing their state or maintaining them after initial creation. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| status | Σ ?! | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.status draft | active | on-hold | revoked | completed | entered-in-error | unknownDefinition The status of the order. The status is generally fully in the control of the requester - they determine whether the order is draft or active and, after it has been activated, competed, cancelled or suspended. States relating to the activities of the performer are reflected on either the corresponding event (see Event Pattern for general discussion) or using the Task resource. The status of a service order.RequestStatus (required)Constraints 
 
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| intent | Σ ?! | 1..1 | codeBindingFixed Value | Element Id ServiceRequest.intent proposal | plan | directive | order | original-order | reflex-order | filler-order | instance-order | optionDefinition Whether the request is a proposal, plan, an original order or a reflex order. This element is labeled as a modifier because the intent alters when and how the resource is actually applicable. The kind of service request.RequestIntent (required)Constraints 
 plan 
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| category | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.category Classification of serviceDefinition A code that classifies the service for searching, sorting and display purposes (e.g. "Surgical Procedure"). Used for filtering what service request are retrieved and displayed. There may be multiple axis of categorization depending on the context or use case for retrieving or displaying the resource. The level of granularity is defined by the category concepts in the value set. Classification of the requested service.ServiceRequestCategoryCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id ServiceRequest.category.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. 
 https://fhir.nhs.uk/CodeSystem/message-category-servicerequest 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | codeFixed Value | Element Id ServiceRequest.category.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 validation 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| priority | Σ | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.priority routine | urgent | asap | statDefinition Indicates how quickly the ServiceRequest should be addressed with respect to other requests. Note that FHIR strings SHALL NOT exceed 1MB in size Identifies the level of importance to be assigned to actioning the request.RequestPriority (required)Constraints 
 
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| doNotPerform | Σ ?! | 0..1 | boolean | There are no (further) constraints on this elementElement Id ServiceRequest.doNotPerform True if service/procedure should not be performedDefinition Set this to true if the record is saying that the service/procedure should NOT be performed. Used for do not ambulate, do not elevate head of bed, do not flush NG tube, do not take blood pressure on a certain arm, etc. In general, only the code and timeframe will be present, though occasional additional qualifiers such as body site or even performer could be included to narrow the scope of the prohibition. If the ServiceRequest.code and ServiceRequest.doNotPerform both contain negation, that will reinforce prohibition and should not have a double negative interpretation. 
 
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| code | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.code What is being requested/orderedAlternate names service requestedDefinition A code that identifies a particular service (i.e., procedure, diagnostic investigation, or panel of investigations) that have been requested. Many laboratory and radiology procedure codes embed the specimen/organ system in the test order name, for example, serum or serum/plasma glucose, or a chest x-ray. The specimen might not be recorded separately from the test code. A set of codes that define a procedure or a procedure with explicit context. Selected from the SNOMED CT UK coding system.UKCoreProcedureCode (preferred)Constraints 
 
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| orderDetail | Σ I | 0..* | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.orderDetail Additional order informationAlternate names detailed instructionsDefinition Additional details and instructions about the how the services are to be delivered. For example, and order for a urinary catheter may have an order detail for an external or indwelling catheter, or an order for a bandage may require additional instructions specifying how the bandage should be applied. For information from the medical record intended to support the delivery of the requested services, use the  Codified order entry details which are based on order context.ServiceRequestOrderDetailsCodes (example)Constraints 
 
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| quantity[x] | Σ | 0..1 | There are no (further) constraints on this elementElement Id ServiceRequest.quantity[x] Service amountDefinition An amount of service being requested which can be a quantity ( for example $1,500 home modification), a ratio ( for example, 20 half day visits per month), or a range (2.0 to 1.8 Gy per fraction). When ordering a service the number of service items may need to be specified separately from the the service item. 
 
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| quantityQuantity | Quantity | There are no (further) constraints on this elementData Type | ||
| quantityRatio | Ratio | There are no (further) constraints on this elementData Type | ||
| quantityRange | Range | There are no (further) constraints on this elementData Type | ||
| subject | Σ I | 1..1 | Reference(UK Core Patient) | Element Id ServiceRequest.subject Individual or Entity the service is ordered forDefinition On whom or what the service is to be performed. This is usually a human patient, but can also be requested on animals, groups of humans or animals, devices such as dialysis machines, or even locations (typically for environmental scans). References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| encounter | Σ I | 0..1 | Reference(UK Core Encounter) | Element Id ServiceRequest.encounter Encounter in which the request was createdAlternate names contextDefinition An encounter that provides additional information about the healthcare context in which this request is made. Encounter context 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| occurrence[x] | Σ | 0..1 | Element Id ServiceRequest.occurrence[x] When service should occurAlternate names scheduleDefinition The date/time at which the requested service should occur. Validation Breach Time/Call back breach time 
 
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| occurrencePeriod | Period | Data Type | ||
| start | Σ I | 1..1 | dateTime | There are no (further) constraints on this elementElement Id ServiceRequest.occurrence[x].start Starting time with inclusive boundaryDefinition The start of the period. The boundary is inclusive. If the low element is missing, the meaning is that the low boundary is not known. 
 
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| end | Σ I | 1..1 | dateTime | There are no (further) constraints on this elementElement Id ServiceRequest.occurrence[x].end End time with inclusive boundary, if not ongoingDefinition The end of the period. If the end of the period is missing, it means no end was known or planned at the time the instance was created. The start may be in the past, and the end date in the future, which means that period is expected/planned to end at that time. The high value includes any matching date/time. i.e. 2012-02-03T10:00:00 is in a period that has an end value of 2012-02-03. 
 
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| asNeeded[x] | Σ | 0..1 | There are no (further) constraints on this elementElement Id ServiceRequest.asNeeded[x] Preconditions for serviceDefinition If a CodeableConcept is present, it indicates the pre-condition for performing the service. For example "pain", "on flare-up", etc. A coded concept identifying the pre-condition that should hold prior to performing a procedure. For example "pain", "on flare-up", etc.SNOMEDCTMedicationAsNeededReasonCodes (example)Constraints 
 
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| asNeededBoolean | boolean | There are no (further) constraints on this elementData Type | ||
| asNeededCodeableConcept | CodeableConcept | There are no (further) constraints on this elementData Type | ||
| authoredOn | Σ | 0..1 | dateTime | Element Id ServiceRequest.authoredOn Date request signedAlternate names orderedOnDefinition When the request transitioned to being actionable. ReferralDateTime 
 
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| requester | Σ I | 0..1 | Reference(UK Core Device | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson) | Element Id ServiceRequest.requester Who/what is requesting serviceAlternate names author, ordererDefinition The individual who initiated the request and has responsibility for its activation. Participant Reference(UK Core Device | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson)Constraints 
 
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| reference | Σ I | 0..1 | string | Element Id ServiceRequest.requester.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Organisation 
 
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| type | Σ | 0..1 | uriBinding | Element Id ServiceRequest.requester.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Service Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requester.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| performerType | Σ | 0..1 | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.performerType Performer roleAlternate names specialtyDefinition Desired type of performer for doing the requested service. This is a role, not a participation type. In other words, does not describe the task but describes the capacity. For example, “compounding pharmacy”, “psychiatrist” or “internal referral”. Indicates specific responsibility of an individual within the care team, such as "Primary physician", "Team coordinator", "Caregiver", etc.ParticipantRoles (example)Constraints 
 
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| performer | Σ I | 0..* | Reference(UK Core CareTeam | UK Core Device | UK Core HealthcareService | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson) | Element Id ServiceRequest.performer Requested performerAlternate names request recipientDefinition The desired performer for doing the requested service. For example, the surgeon, dermatopathologist, endoscopist, etc. Referral To Reference(UK Core CareTeam | UK Core Device | UK Core HealthcareService | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| locationCode | Σ | 0..* | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.locationCode Requested locationDefinition The preferred location(s) where the procedure should actually happen in coded or free text form. E.g. at home or nursing day care center. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. A location type where services are delivered.v3.ServiceDeliveryLocationRoleType (example)Constraints 
 
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| locationReference | Σ I | 0..* | Reference(UK Core Location) | Element Id ServiceRequest.locationReference Requested locationDefinition A reference to the the preferred location(s) where the procedure should actually happen. E.g. at home or nursing day care center. Incident location 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reasonCode | Σ | 0..* | CodeableConceptBinding | Element Id ServiceRequest.reasonCode Explanation/Justification for procedure or serviceDefinition An explanation or justification for why this service is being requested in coded or textual form.   This is often for billing purposes.  May relate to the resources referred to in  Reason for referral/Next activity/Clinical Urgency of Referral A set of codes that define a reason for a service request.UKCoreServiceRequestReasonCode (extensible)Constraints 
 
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| coding | Σ | 0..* | Coding | Element Id ServiceRequest.reasonCode.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Proprietary Triage Outcome code system 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonCode.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| reasonReference | Σ I | 0..* | Reference(UK Core Condition | UK Core DiagnosticReport | UK Core DocumentReference | UK Core Observation) | Element Id ServiceRequest.reasonReference Explanation/Justification for service or serviceDefinition Indicates another resource that provides a justification for why this service is being requested.   May relate to the resources referred to in  Chief concern Reference(UK Core Condition | UK Core DiagnosticReport | UK Core DocumentReference | UK Core Observation)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| insurance | I | 0..* | Reference(Coverage | ClaimResponse) | There are no (further) constraints on this elementElement Id ServiceRequest.insurance Associated insurance coverageDefinition Insurance plans, coverage extensions, pre-authorizations and/or pre-determinations that may be needed for delivering the requested service. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(Coverage | ClaimResponse)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| supportingInfo | I | 0..* | Reference(Resource) | Element Id ServiceRequest.supportingInfo Additional clinical informationAlternate names Ask at order entry question, AOEDefinition Additional clinical information about the patient or specimen that may influence the services or their interpretations. This information includes diagnosis, clinical findings and other observations. In laboratory ordering these are typically referred to as "ask at order entry questions (AOEs)". This includes observations explicitly requested by the producer (filler) to provide context or supporting information needed to complete the order. For example, reporting the amount of inspired oxygen for blood gas measurements. Rejected Services/patient choice (QuestionnaireResponse), Secondary concern (Condition) 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| specimen | Σ I | 0..* | Reference(UK Core Specimen) | There are no (further) constraints on this elementElement Id ServiceRequest.specimen Procedure SamplesDefinition One or more specimens that the laboratory procedure will use. Many diagnostic procedures need a specimen, but the request itself is not actually about the specimen. This element is for when the diagnostic is requested on already existing specimens and the request points to the specimen it applies to. Conversely, if the request is entered first with an unknown specimen, then the Specimen resource points to the ServiceRequest. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| bodySite | Σ | 0..* | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.bodySite Location on BodyAlternate names locationDefinition Anatomic location where the procedure should be performed. This is the target site. Knowing where the procedure is performed is important for tracking if multiple sites are possible. Only used if not implicit in the code found in ServiceRequest.code. If the use case requires BodySite to be handled as a separate resource instead of an inline coded element (e.g. to identify and track separately) then use the standard extension procedure-targetBodyStructure. A set of codes that define an anatomical or acquired body structure site. Selected from the SNOMED CT UK coding system.UKCoreBodySite (extensible)Constraints 
 
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| note | 0..* | Annotation | There are no (further) constraints on this elementElement Id ServiceRequest.note CommentsDefinition Any other notes and comments made about the service request. For example, internal billing notes. For systems that do not have structured annotations, they can simply communicate a single annotation with no author or time. This element may need to be included in narrative because of the potential for modifying information. Annotations SHOULD NOT be used to communicate "modifying" information that could be computable. (This is a SHOULD because enforcing user behavior is nearly impossible). 
 
 | |
| patientInstruction | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.patientInstruction Patient or consumer-oriented instructionsDefinition Instructions in terms that are understood by the patient or consumer. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| relevantHistory | I | 0..* | Reference(UK Core Provenance) | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory Request provenanceDefinition Key events in the history of the request. This might not include provenances for all versions of the request – only those deemed “relevant” or important. This SHALL NOT include the Provenance associated with this current version of the resource. (If that provenance is deemed to be a “relevant” change, it will need to be added as part of a later update. Until then, it can be queried directly as the Provenance that points to this version using _revinclude All Provenances should have some historical version of this Request as their subject. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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Snapshot View
| ServiceRequest | I | ServiceRequest | There are no (further) constraints on this elementElement Id ServiceRequest A request for a service to be performedAlternate names diagnostic request, referral, referral request, transfer of care requestDefinition A record of a request for service such as diagnostic investigations, treatments, or operations to be performed. 
 
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| extension | I | 0..* | Extension | There are no (further) constraints on this elementElement Id ServiceRequest.extension Additional content defined by implementationsAlternate names extensions, user contentDefinition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Unordered, Open, by url(Value)Constraints 
 
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| sourceOfServiceRequest | I | 0..1 | Extension(CodeableConcept) | There are no (further) constraints on this elementElement Id ServiceRequest.extension:sourceOfServiceRequest This represents the source of referralAlternate names extensions, user contentDefinition This represents the source of referral. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. https://fhir.hl7.org.uk/StructureDefinition/Extension-UKCore-SourceOfServiceRequestConstraints 
 
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| identifier | Σ | 0..* | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.identifier Identifiers assigned to this orderDefinition Identifiers assigned to this order instance by the orderer and/or the receiver and/or order fulfiller. The identifier.type element is used to distinguish between the identifiers assigned by the orderer (known as the 'Placer' in HL7 v2) and the producer of the observations in response to the order (known as the 'Filler' in HL7 v2). For further discussion and examples see the resource notes section below. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| instantiatesCanonical | Σ | 0..* | canonical(ActivityDefinition | PlanDefinition) | There are no (further) constraints on this elementElement Id ServiceRequest.instantiatesCanonical Instantiates FHIR protocol or definitionDefinition The URL pointing to a FHIR-defined protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest. Note: This is a business identifier, not a resource identifier (see discussion). It is best practice for the identifier to only appear on a single resource instance, however business practices may occasionally dictate that multiple resource instances with the same identifier can exist - possibly even with different resource types. For example, multiple Patient and a Person resource instance might share the same social insurance number. canonical(ActivityDefinition | PlanDefinition)Constraints 
 
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| instantiatesUri | Σ | 0..* | uri | There are no (further) constraints on this elementElement Id ServiceRequest.instantiatesUri Instantiates external protocol or definitionDefinition The URL pointing to an externally maintained protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest. This might be an HTML page, PDF, etc. or could just be a non-resolvable URI identifier. 
 
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| basedOn | Σ I | 0..* | Reference(UK Core CarePlan | UK Core MedicationRequest | UK Core ServiceRequest) | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn What request fulfillsAlternate names fulfillsDefinition Plan/proposal/order fulfilled by this request. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core CarePlan | UK Core MedicationRequest | UK Core ServiceRequest)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.basedOn.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| replaces | Σ I | 0..* | Reference(UK Core ServiceRequest) | There are no (further) constraints on this elementElement Id ServiceRequest.replaces What request replacesAlternate names supersedes, prior, renewed orderDefinition The request takes the place of the referenced completed or terminated request(s). References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(UK Core ServiceRequest)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.replaces.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| requisition | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.requisition Composite Request IDAlternate names grouperId, groupIdentifierDefinition A shared identifier common to all service requests that were authorized more or less simultaneously by a single author, representing the composite or group identifier. Some business processes need to know if multiple items were ordered as part of the same "requisition" for billing or other purposes. Requests are linked either by a "basedOn" relationship (i.e. one request is fulfilling another) or by having a common requisition. Requests that are part of the same requisition are generally treated independently from the perspective of changing their state or maintaining them after initial creation. 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.requisition.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| status | Σ ?! | 1..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.status draft | active | on-hold | revoked | completed | entered-in-error | unknownDefinition The status of the order. The status is generally fully in the control of the requester - they determine whether the order is draft or active and, after it has been activated, competed, cancelled or suspended. States relating to the activities of the performer are reflected on either the corresponding event (see Event Pattern for general discussion) or using the Task resource. The status of a service order.RequestStatus (required)Constraints 
 
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| intent | Σ ?! | 1..1 | codeBindingFixed Value | Element Id ServiceRequest.intent proposal | plan | directive | order | original-order | reflex-order | filler-order | instance-order | optionDefinition Whether the request is a proposal, plan, an original order or a reflex order. This element is labeled as a modifier because the intent alters when and how the resource is actually applicable. The kind of service request.RequestIntent (required)Constraints 
 plan 
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| category | Σ | 1..1 | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.category Classification of serviceDefinition A code that classifies the service for searching, sorting and display purposes (e.g. "Surgical Procedure"). Used for filtering what service request are retrieved and displayed. There may be multiple axis of categorization depending on the context or use case for retrieving or displaying the resource. The level of granularity is defined by the category concepts in the value set. Classification of the requested service.ServiceRequestCategoryCodes (example)Constraints 
 
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| coding | Σ | 0..* | Coding | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. 
 
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| system | Σ | 0..1 | uriFixed Value | Element Id ServiceRequest.category.coding.system Identity of the terminology systemDefinition The identification of the code system that defines the meaning of the symbol in the code. Need to be unambiguous about the source of the definition of the symbol. The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. 
 https://fhir.nhs.uk/CodeSystem/message-category-servicerequest 
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| version | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.version Version of the system - if relevantDefinition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. 
 
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| code | Σ | 0..1 | codeFixed Value | Element Id ServiceRequest.category.coding.code Symbol in syntax defined by the systemDefinition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Need to refer to a particular code in the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 validation 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.display Representation defined by the systemDefinition A representation of the meaning of the code in the system, following the rules of the system. Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| userSelected | Σ | 0..1 | boolean | There are no (further) constraints on this elementElement Id ServiceRequest.category.coding.userSelected If this coding was chosen directly by the userDefinition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.category.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| priority | Σ | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.priority routine | urgent | asap | statDefinition Indicates how quickly the ServiceRequest should be addressed with respect to other requests. Note that FHIR strings SHALL NOT exceed 1MB in size Identifies the level of importance to be assigned to actioning the request.RequestPriority (required)Constraints 
 
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| doNotPerform | Σ ?! | 0..1 | boolean | There are no (further) constraints on this elementElement Id ServiceRequest.doNotPerform True if service/procedure should not be performedDefinition Set this to true if the record is saying that the service/procedure should NOT be performed. Used for do not ambulate, do not elevate head of bed, do not flush NG tube, do not take blood pressure on a certain arm, etc. In general, only the code and timeframe will be present, though occasional additional qualifiers such as body site or even performer could be included to narrow the scope of the prohibition. If the ServiceRequest.code and ServiceRequest.doNotPerform both contain negation, that will reinforce prohibition and should not have a double negative interpretation. 
 
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| code | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.code What is being requested/orderedAlternate names service requestedDefinition A code that identifies a particular service (i.e., procedure, diagnostic investigation, or panel of investigations) that have been requested. Many laboratory and radiology procedure codes embed the specimen/organ system in the test order name, for example, serum or serum/plasma glucose, or a chest x-ray. The specimen might not be recorded separately from the test code. A set of codes that define a procedure or a procedure with explicit context. Selected from the SNOMED CT UK coding system.UKCoreProcedureCode (preferred)Constraints 
 
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| orderDetail | Σ I | 0..* | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.orderDetail Additional order informationAlternate names detailed instructionsDefinition Additional details and instructions about the how the services are to be delivered. For example, and order for a urinary catheter may have an order detail for an external or indwelling catheter, or an order for a bandage may require additional instructions specifying how the bandage should be applied. For information from the medical record intended to support the delivery of the requested services, use the  Codified order entry details which are based on order context.ServiceRequestOrderDetailsCodes (example)Constraints 
 
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| quantity[x] | Σ | 0..1 | There are no (further) constraints on this elementElement Id ServiceRequest.quantity[x] Service amountDefinition An amount of service being requested which can be a quantity ( for example $1,500 home modification), a ratio ( for example, 20 half day visits per month), or a range (2.0 to 1.8 Gy per fraction). When ordering a service the number of service items may need to be specified separately from the the service item. 
 
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| quantityQuantity | Quantity | There are no (further) constraints on this elementData Type | ||
| quantityRatio | Ratio | There are no (further) constraints on this elementData Type | ||
| quantityRange | Range | There are no (further) constraints on this elementData Type | ||
| subject | Σ I | 1..1 | Reference(UK Core Patient) | Element Id ServiceRequest.subject Individual or Entity the service is ordered forDefinition On whom or what the service is to be performed. This is usually a human patient, but can also be requested on animals, groups of humans or animals, devices such as dialysis machines, or even locations (typically for environmental scans). References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.subject.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.subject.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| encounter | Σ I | 0..1 | Reference(UK Core Encounter) | Element Id ServiceRequest.encounter Encounter in which the request was createdAlternate names contextDefinition An encounter that provides additional information about the healthcare context in which this request is made. Encounter context 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.encounter.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| occurrence[x] | Σ | 0..1 | Element Id ServiceRequest.occurrence[x] When service should occurAlternate names scheduleDefinition The date/time at which the requested service should occur. Validation Breach Time/Call back breach time 
 
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| occurrencePeriod | Period | Data Type | ||
| start | Σ I | 1..1 | dateTime | There are no (further) constraints on this elementElement Id ServiceRequest.occurrence[x].start Starting time with inclusive boundaryDefinition The start of the period. The boundary is inclusive. If the low element is missing, the meaning is that the low boundary is not known. 
 
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| end | Σ I | 1..1 | dateTime | There are no (further) constraints on this elementElement Id ServiceRequest.occurrence[x].end End time with inclusive boundary, if not ongoingDefinition The end of the period. If the end of the period is missing, it means no end was known or planned at the time the instance was created. The start may be in the past, and the end date in the future, which means that period is expected/planned to end at that time. The high value includes any matching date/time. i.e. 2012-02-03T10:00:00 is in a period that has an end value of 2012-02-03. 
 
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| asNeeded[x] | Σ | 0..1 | There are no (further) constraints on this elementElement Id ServiceRequest.asNeeded[x] Preconditions for serviceDefinition If a CodeableConcept is present, it indicates the pre-condition for performing the service. For example "pain", "on flare-up", etc. A coded concept identifying the pre-condition that should hold prior to performing a procedure. For example "pain", "on flare-up", etc.SNOMEDCTMedicationAsNeededReasonCodes (example)Constraints 
 
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| asNeededBoolean | boolean | There are no (further) constraints on this elementData Type | ||
| asNeededCodeableConcept | CodeableConcept | There are no (further) constraints on this elementData Type | ||
| authoredOn | Σ | 0..1 | dateTime | Element Id ServiceRequest.authoredOn Date request signedAlternate names orderedOnDefinition When the request transitioned to being actionable. ReferralDateTime 
 
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| requester | Σ I | 0..1 | Reference(UK Core Device | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson) | Element Id ServiceRequest.requester Who/what is requesting serviceAlternate names author, ordererDefinition The individual who initiated the request and has responsibility for its activation. Participant Reference(UK Core Device | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson)Constraints 
 
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| reference | Σ I | 0..1 | string | Element Id ServiceRequest.requester.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Organisation 
 
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| type | Σ | 0..1 | uriBinding | Element Id ServiceRequest.requester.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Service Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.requester.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.requester.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| performerType | Σ | 0..1 | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.performerType Performer roleAlternate names specialtyDefinition Desired type of performer for doing the requested service. This is a role, not a participation type. In other words, does not describe the task but describes the capacity. For example, “compounding pharmacy”, “psychiatrist” or “internal referral”. Indicates specific responsibility of an individual within the care team, such as "Primary physician", "Team coordinator", "Caregiver", etc.ParticipantRoles (example)Constraints 
 
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| performer | Σ I | 0..* | Reference(UK Core CareTeam | UK Core Device | UK Core HealthcareService | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson) | Element Id ServiceRequest.performer Requested performerAlternate names request recipientDefinition The desired performer for doing the requested service. For example, the surgeon, dermatopathologist, endoscopist, etc. Referral To Reference(UK Core CareTeam | UK Core Device | UK Core HealthcareService | UK Core Organization | UK Core Patient | UK Core Practitioner | UK Core PractitionerRole | UK Core RelatedPerson)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.performer.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.performer.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| locationCode | Σ | 0..* | CodeableConcept | There are no (further) constraints on this elementElement Id ServiceRequest.locationCode Requested locationDefinition The preferred location(s) where the procedure should actually happen in coded or free text form. E.g. at home or nursing day care center. Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination. A location type where services are delivered.v3.ServiceDeliveryLocationRoleType (example)Constraints 
 
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| locationReference | Σ I | 0..* | Reference(UK Core Location) | Element Id ServiceRequest.locationReference Requested locationDefinition A reference to the the preferred location(s) where the procedure should actually happen. E.g. at home or nursing day care center. Incident location 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.locationReference.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| reasonCode | Σ | 0..* | CodeableConceptBinding | Element Id ServiceRequest.reasonCode Explanation/Justification for procedure or serviceDefinition An explanation or justification for why this service is being requested in coded or textual form.   This is often for billing purposes.  May relate to the resources referred to in  Reason for referral/Next activity/Clinical Urgency of Referral A set of codes that define a reason for a service request.UKCoreServiceRequestReasonCode (extensible)Constraints 
 
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| coding | Σ | 0..* | Coding | Element Id ServiceRequest.reasonCode.coding Code defined by a terminology systemDefinition A reference to a code defined by a terminology system. Allows for alternative encodings within a code system, and translations to other code systems. Proprietary Triage Outcome code system 
 
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| text | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonCode.text Plain text representation of the conceptDefinition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Very often the text is the same as a displayName of one of the codings. 
 
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| reasonReference | Σ I | 0..* | Reference(UK Core Condition | UK Core DiagnosticReport | UK Core DocumentReference | UK Core Observation) | Element Id ServiceRequest.reasonReference Explanation/Justification for service or serviceDefinition Indicates another resource that provides a justification for why this service is being requested.   May relate to the resources referred to in  Chief concern Reference(UK Core Condition | UK Core DiagnosticReport | UK Core DocumentReference | UK Core Observation)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.reasonReference.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| insurance | I | 0..* | Reference(Coverage | ClaimResponse) | There are no (further) constraints on this elementElement Id ServiceRequest.insurance Associated insurance coverageDefinition Insurance plans, coverage extensions, pre-authorizations and/or pre-determinations that may be needed for delivering the requested service. References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Reference(Coverage | ClaimResponse)Constraints 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.insurance.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| supportingInfo | I | 0..* | Reference(Resource) | Element Id ServiceRequest.supportingInfo Additional clinical informationAlternate names Ask at order entry question, AOEDefinition Additional clinical information about the patient or specimen that may influence the services or their interpretations. This information includes diagnosis, clinical findings and other observations. In laboratory ordering these are typically referred to as "ask at order entry questions (AOEs)". This includes observations explicitly requested by the producer (filler) to provide context or supporting information needed to complete the order. For example, reporting the amount of inspired oxygen for blood gas measurements. Rejected Services/patient choice (QuestionnaireResponse), Secondary concern (Condition) 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.supportingInfo.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| specimen | Σ I | 0..* | Reference(UK Core Specimen) | There are no (further) constraints on this elementElement Id ServiceRequest.specimen Procedure SamplesDefinition One or more specimens that the laboratory procedure will use. Many diagnostic procedures need a specimen, but the request itself is not actually about the specimen. This element is for when the diagnostic is requested on already existing specimens and the request points to the specimen it applies to. Conversely, if the request is entered first with an unknown specimen, then the Specimen resource points to the ServiceRequest. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
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| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
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| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
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| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
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| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
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| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
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| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
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| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
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| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
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| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.specimen.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
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| bodySite | Σ | 0..* | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.bodySite Location on BodyAlternate names locationDefinition Anatomic location where the procedure should be performed. This is the target site. Knowing where the procedure is performed is important for tracking if multiple sites are possible. Only used if not implicit in the code found in ServiceRequest.code. If the use case requires BodySite to be handled as a separate resource instead of an inline coded element (e.g. to identify and track separately) then use the standard extension procedure-targetBodyStructure. A set of codes that define an anatomical or acquired body structure site. Selected from the SNOMED CT UK coding system.UKCoreBodySite (extensible)Constraints 
 
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| note | 0..* | Annotation | There are no (further) constraints on this elementElement Id ServiceRequest.note CommentsDefinition Any other notes and comments made about the service request. For example, internal billing notes. For systems that do not have structured annotations, they can simply communicate a single annotation with no author or time. This element may need to be included in narrative because of the potential for modifying information. Annotations SHOULD NOT be used to communicate "modifying" information that could be computable. (This is a SHOULD because enforcing user behavior is nearly impossible). 
 
 | |
| patientInstruction | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.patientInstruction Patient or consumer-oriented instructionsDefinition Instructions in terms that are understood by the patient or consumer. Note that FHIR strings SHALL NOT exceed 1MB in size 
 
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| relevantHistory | I | 0..* | Reference(UK Core Provenance) | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory Request provenanceDefinition Key events in the history of the request. This might not include provenances for all versions of the request – only those deemed “relevant” or important. This SHALL NOT include the Provenance associated with this current version of the resource. (If that provenance is deemed to be a “relevant” change, it will need to be added as part of a later update. Until then, it can be queried directly as the Provenance that points to this version using _revinclude All Provenances should have some historical version of this Request as their subject. 
 
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| reference | Σ I | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.reference Literal reference, Relative, internal or absolute URLDefinition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. 
 
 | 
| type | Σ | 0..1 | uriBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.type Type the reference refers to (e.g. "Patient")Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Aa resource (or, for logical models, the URI of the logical model).ResourceType (extensible)Constraints 
 
 | 
| identifier | Σ | 0..1 | Identifier | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier Logical reference, when literal reference is not knownDefinition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). 
 
 | 
| use | Σ ?! | 0..1 | codeBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.use usual | official | temp | secondary | old (If known)Definition The purpose of this identifier. Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Identifies the purpose for this identifier, if known .IdentifierUse (required)Constraints 
 
 | 
| type | Σ | 0..1 | CodeableConceptBinding | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.type Description of identifierDefinition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Allows users to make use of identifiers when the identifier system is not known. This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.Identifier Type Codes (extensible)Constraints 
 
 | 
| system | Σ | 0..1 | uri | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.system The namespace for the identifier valueDefinition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Identifier.system is always case sensitive. 
 General http://www.acme.com/identifiers/patient Mappings 
 | 
| value | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.value The value that is uniqueDefinition The portion of the identifier typically relevant to the user and which is unique within the context of the system. If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. 
 General 123456 Mappings 
 | 
| period | Σ I | 0..1 | Period | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.period Time period when id is/was valid for useDefinition Time period during which identifier is/was valid for use. A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. 
 
 | 
| assigner | Σ I | 0..1 | Reference(UK Core Organization) | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.identifier.assigner Organization that issued id (may be just text)Definition Organization that issued/manages the identifier. The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Reference(UK Core Organization)Constraints 
 
 | 
| display | Σ | 0..1 | string | There are no (further) constraints on this elementElement Id ServiceRequest.relevantHistory.display Text alternative for the resourceDefinition Plain text narrative that identifies the resource in addition to the resource reference. This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. 
 
 | 
Examples
BARS MessageDefinition Booking-Request
Defines the constraints and extensions on the UKCore-Bundle FHIR Profile
Based on: UKCore.Release1@1.0.1/package/UKCore-Bundle
Differential View
| MessageDefinition | 
| id : 95b337c0-9644-4b5e-accf-246636e55905 | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-booking-request | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition Booking - Request | 
| title : BARS Message Definition Booking - Request | 
| status : active | 
| date : 2022-02-11 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : booking-request | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-booking-request | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-referral | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 0 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 0 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Appointment | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Appointment | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Slot | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Slot | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Schedule | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Schedule | 
| min : 1 | 
| max : 1 | 
Hybrid View
| MessageDefinition | 
| id : 95b337c0-9644-4b5e-accf-246636e55905 | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-booking-request | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition Booking - Request | 
| title : BARS Message Definition Booking - Request | 
| status : active | 
| date : 2022-02-11 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : booking-request | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-booking-request | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-referral | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 0 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 0 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Appointment | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Appointment | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Slot | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Slot | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Schedule | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Schedule | 
| min : 1 | 
| max : 1 | 
Snapshot View
| MessageDefinition | 
| id : 95b337c0-9644-4b5e-accf-246636e55905 | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-booking-request | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition Booking - Request | 
| title : BARS Message Definition Booking - Request | 
| status : active | 
| date : 2022-02-11 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : booking-request | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-booking-request | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-referral | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 0 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 0 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Appointment | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Appointment | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Slot | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Slot | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Schedule | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Schedule | 
| min : 1 | 
| max : 1 | 
BARS MessageDefinition ServiceRequest-RequestReferral
Defines the constraints and extensions on the UKCore-Bundle FHIR Profile
Based on: UKCore.Release1@1.0.1/package/UKCore-Bundle
Differential View
| MessageDefinition | 
| id : 11882ae2-211f-49ee-acbe-e319304d80cd | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-request-referral | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Request Referral | 
| title : BARS Message Definition ServiceRequest - Request Referral | 
| status : active | 
| date : 2022-02-11 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-request | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-request | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-referral | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : CarePlan | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-CarePlan | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 1 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 1 | 
| max : * | 
| focus | 
| code : Observation | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | 
| min : 0 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : http://hl7.org/fhir/StructureDefinition/Flag | 
| min : 0 | 
| max : * | 
| focus | 
| code : MedicationStatement | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-MedicationStatement | 
| min : 0 | 
| max : * | 
| focus | 
| code : AllergyIntolerance | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-AllergyIntolerance | 
| min : 0 | 
| max : * | 
| focus | 
| code : QuestionnaireResponse | 
| profile : http://hl7.org/fhir/StructureDefinition/QuestionnaireResponse | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 1 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
Hybrid View
| MessageDefinition | 
| id : 11882ae2-211f-49ee-acbe-e319304d80cd | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-request-referral | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Request Referral | 
| title : BARS Message Definition ServiceRequest - Request Referral | 
| status : active | 
| date : 2022-02-11 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-request | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-request | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-referral | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : CarePlan | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-CarePlan | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 1 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 1 | 
| max : * | 
| focus | 
| code : Observation | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | 
| min : 0 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : http://hl7.org/fhir/StructureDefinition/Flag | 
| min : 0 | 
| max : * | 
| focus | 
| code : MedicationStatement | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-MedicationStatement | 
| min : 0 | 
| max : * | 
| focus | 
| code : AllergyIntolerance | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-AllergyIntolerance | 
| min : 0 | 
| max : * | 
| focus | 
| code : QuestionnaireResponse | 
| profile : http://hl7.org/fhir/StructureDefinition/QuestionnaireResponse | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 1 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
Snapshot View
| MessageDefinition | 
| id : 11882ae2-211f-49ee-acbe-e319304d80cd | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-request-referral | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Request Referral | 
| title : BARS Message Definition ServiceRequest - Request Referral | 
| status : active | 
| date : 2022-02-11 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-request | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-request | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-referral | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : CarePlan | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-CarePlan | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 1 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 1 | 
| max : * | 
| focus | 
| code : Observation | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | 
| min : 0 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : http://hl7.org/fhir/StructureDefinition/Flag | 
| min : 0 | 
| max : * | 
| focus | 
| code : MedicationStatement | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-MedicationStatement | 
| min : 0 | 
| max : * | 
| focus | 
| code : AllergyIntolerance | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-AllergyIntolerance | 
| min : 0 | 
| max : * | 
| focus | 
| code : QuestionnaireResponse | 
| profile : http://hl7.org/fhir/StructureDefinition/QuestionnaireResponse | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 1 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
BARS MessageDefinition ServiceRequest-ResponseReferral
Defines the constraints and extensions on the UKCore-Bundle FHIR Profile
Based on: UKCore.Release1@1.0.1/package/UKCore-Bundle
Differential View
| MessageDefinition | 
| id : 2a2ff4ff-47cd-4094-a95e-e8179e6f48b8 | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-response-referral | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Response Referral | 
| title : BARS Message Definition ServiceRequest - Response Referral | 
| status : active | 
| date : 2022-02-11 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-response | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-request | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-referral | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : CarePlan | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-CarePlan | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 1 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 1 | 
| max : * | 
| focus | 
| code : Observation | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | 
| min : 0 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : http://hl7.org/fhir/StructureDefinition/Flag | 
| min : 0 | 
| max : * | 
| focus | 
| code : MedicationStatement | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-MedicationStatement | 
| min : 0 | 
| max : * | 
| focus | 
| code : AllergyIntolerance | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-AllergyIntolerance | 
| min : 0 | 
| max : * | 
| focus | 
| code : QuestionnaireResponse | 
| profile : http://hl7.org/fhir/StructureDefinition/QuestionnaireResponse | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 1 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Appointment | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Appointment | 
| min : 0 | 
| max : 1 | 
Hybrid View
| MessageDefinition | 
| id : 2a2ff4ff-47cd-4094-a95e-e8179e6f48b8 | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-response-referral | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Response Referral | 
| title : BARS Message Definition ServiceRequest - Response Referral | 
| status : active | 
| date : 2022-02-11 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-response | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-request | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-referral | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : CarePlan | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-CarePlan | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 1 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 1 | 
| max : * | 
| focus | 
| code : Observation | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | 
| min : 0 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : http://hl7.org/fhir/StructureDefinition/Flag | 
| min : 0 | 
| max : * | 
| focus | 
| code : MedicationStatement | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-MedicationStatement | 
| min : 0 | 
| max : * | 
| focus | 
| code : AllergyIntolerance | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-AllergyIntolerance | 
| min : 0 | 
| max : * | 
| focus | 
| code : QuestionnaireResponse | 
| profile : http://hl7.org/fhir/StructureDefinition/QuestionnaireResponse | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 1 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Appointment | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Appointment | 
| min : 0 | 
| max : 1 | 
Snapshot View
| MessageDefinition | 
| id : 2a2ff4ff-47cd-4094-a95e-e8179e6f48b8 | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-response-referral | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Response Referral | 
| title : BARS Message Definition ServiceRequest - Response Referral | 
| status : active | 
| date : 2022-02-11 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-response | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-request | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-referral | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : CarePlan | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-CarePlan | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 0 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 1 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 1 | 
| max : * | 
| focus | 
| code : Observation | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | 
| min : 0 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : http://hl7.org/fhir/StructureDefinition/Flag | 
| min : 0 | 
| max : * | 
| focus | 
| code : MedicationStatement | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-MedicationStatement | 
| min : 0 | 
| max : * | 
| focus | 
| code : AllergyIntolerance | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-AllergyIntolerance | 
| min : 0 | 
| max : * | 
| focus | 
| code : QuestionnaireResponse | 
| profile : http://hl7.org/fhir/StructureDefinition/QuestionnaireResponse | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 1 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Appointment | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Appointment | 
| min : 0 | 
| max : 1 | 
BARS MessageDefinition ServiceRequest-RequestValidation
Defines the constraints and extensions on the UKCore-Bundle FHIR Profile
Based on: UKCore.Release1@1.0.1/package/UKCore-Bundle
Differential View
| MessageDefinition | 
| id : 7731af63-04ed-47d9-8f05-e510dece3b3f | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-request-validation | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Request Validation | 
| title : BARS Message Definition ServiceRequest - Request Validation | 
| status : active | 
| date : 2021-12-08 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-request | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-request | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-validation | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : CarePlan | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-CarePlan | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 1 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 1 | 
| max : * | 
| focus | 
| code : Observation | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | 
| min : 0 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSFlag-scene-safety | 
| min : 1 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : http://hl7.org/fhir/StructureDefinition/Flag | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 1 | 
| max : * | 
| focus | 
| code : MedicationStatement | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-MedicationStatement | 
| min : 0 | 
| max : * | 
| focus | 
| code : AllergyIntolerance | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-AllergyIntolerance | 
| min : 0 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
Hybrid View
| MessageDefinition | 
| id : 7731af63-04ed-47d9-8f05-e510dece3b3f | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-request-validation | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Request Validation | 
| title : BARS Message Definition ServiceRequest - Request Validation | 
| status : active | 
| date : 2021-12-08 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-request | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-request | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-validation | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : CarePlan | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-CarePlan | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 1 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 1 | 
| max : * | 
| focus | 
| code : Observation | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | 
| min : 0 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSFlag-scene-safety | 
| min : 1 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : http://hl7.org/fhir/StructureDefinition/Flag | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 1 | 
| max : * | 
| focus | 
| code : MedicationStatement | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-MedicationStatement | 
| min : 0 | 
| max : * | 
| focus | 
| code : AllergyIntolerance | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-AllergyIntolerance | 
| min : 0 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
Snapshot View
| MessageDefinition | 
| id : 7731af63-04ed-47d9-8f05-e510dece3b3f | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-request-validation | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Request Validation | 
| title : BARS Message Definition ServiceRequest - Request Validation | 
| status : active | 
| date : 2021-12-08 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-request | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-request | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-validation | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : CarePlan | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-CarePlan | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 1 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 1 | 
| max : * | 
| focus | 
| code : Observation | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | 
| min : 0 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSFlag-scene-safety | 
| min : 1 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : http://hl7.org/fhir/StructureDefinition/Flag | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 1 | 
| max : * | 
| focus | 
| code : MedicationStatement | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-MedicationStatement | 
| min : 0 | 
| max : * | 
| focus | 
| code : AllergyIntolerance | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-AllergyIntolerance | 
| min : 0 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
BARS MessageDefinition ServiceRequest-ResponseValidationInterim
Defines the constraints and extensions on the UKCore-Bundle FHIR Profile
Based on: UKCore.Release1@1.0.1/package/UKCore-Bundle
Differential View
| MessageDefinition | 
| id : 15b429dc-2464-42ca-b401-4c2a5e8320bb | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-response-validation-interim | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Response Validation Interim | 
| title : BARS Message Definition ServiceRequest - Response Validation Interim | 
| status : active | 
| date : 2022-05-31 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-response | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-response | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-validation | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 2 | 
| max : 3 | 
Hybrid View
| MessageDefinition | 
| id : 15b429dc-2464-42ca-b401-4c2a5e8320bb | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-response-validation-interim | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Response Validation Interim | 
| title : BARS Message Definition ServiceRequest - Response Validation Interim | 
| status : active | 
| date : 2022-05-31 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-response | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-response | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-validation | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 2 | 
| max : 3 | 
Snapshot View
| MessageDefinition | 
| id : 15b429dc-2464-42ca-b401-4c2a5e8320bb | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-response-validation-interim | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Response Validation Interim | 
| title : BARS Message Definition ServiceRequest - Response Validation Interim | 
| status : active | 
| date : 2022-05-31 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-response | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-response | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-validation | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 2 | 
| max : 3 | 
BARS MessageDefinition ServiceRequest-ResponseValidationFull
Defines the constraints and extensions on the UKCore-Bundle FHIR Profile
Based on: UKCore.Release1@1.0.1/package/UKCore-Bundle
Differential View
| MessageDefinition | 
| id : 15b429dc-2464-42ca-b401-4c2a5e8320aa | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-response-validation-full | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Response Validation Full | 
| title : BARS Message Definition ServiceRequest - Response Validation Full | 
| status : active | 
| date : 2022-05-31 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-response | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-response | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-validation | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 2 | 
| max : 3 | 
| focus | 
| code : CarePlan | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-CarePlan | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 1 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 1 | 
| max : * | 
| focus | 
| code : Observation | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | 
| min : 0 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSFlag-scene-safety | 
| min : 1 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : http://hl7.org/fhir/StructureDefinition/Flag | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 1 | 
| max : * | 
| focus | 
| code : MedicationStatement | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-MedicationStatement | 
| min : 0 | 
| max : * | 
| focus | 
| code : AllergyIntolerance | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-AllergyIntolerance | 
| min : 0 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
Hybrid View
| MessageDefinition | 
| id : 15b429dc-2464-42ca-b401-4c2a5e8320aa | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-response-validation-full | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Response Validation Full | 
| title : BARS Message Definition ServiceRequest - Response Validation Full | 
| status : active | 
| date : 2022-05-31 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-response | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-response | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-validation | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 2 | 
| max : 3 | 
| focus | 
| code : CarePlan | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-CarePlan | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 1 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 1 | 
| max : * | 
| focus | 
| code : Observation | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | 
| min : 0 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSFlag-scene-safety | 
| min : 1 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : http://hl7.org/fhir/StructureDefinition/Flag | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 1 | 
| max : * | 
| focus | 
| code : MedicationStatement | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-MedicationStatement | 
| min : 0 | 
| max : * | 
| focus | 
| code : AllergyIntolerance | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-AllergyIntolerance | 
| min : 0 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 | 
Snapshot View
| MessageDefinition | 
| id : 15b429dc-2464-42ca-b401-4c2a5e8320aa | 
| url : https://fhir.nhs.uk/MessageDefinition/bars-message-servicerequest-response-validation-full | 
| version : 1.0.0-alpha | 
| name : BARS Message Definition ServiceRequest - Response Validation Full | 
| title : BARS Message Definition ServiceRequest - Response Validation Full | 
| status : active | 
| date : 2022-05-31 | 
| useContext | 
| code | 
| system : https://fhir.nhs.uk/CodeSystem/dos-id | 
| code : dos-id | 
| value | 
| coding | 
| system : http://terminology.hl7.org/CodeSystem/variant-state | 
| code : positive | 
| event | 
| system : https://fhir.nhs.uk/CodeSystem/message-events-bars | 
| code : servicerequest-response | 
| focus | 
| code : Bundle | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSBundleMessage | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : MessageHeader | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSMessageHeader-servicerequest-response | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : ServiceRequest | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSServiceRequest-request-validation | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Patient | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Patient | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Encounter | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Encounter | 
| min : 2 | 
| max : 3 | 
| focus | 
| code : CarePlan | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-CarePlan | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Location | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | 
| min : 1 | 
| max : 1 | 
| focus | 
| code : Organization | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Organization | 
| min : 2 | 
| max : * | 
| focus | 
| code : Practitioner | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Practitioner | 
| min : 1 | 
| max : * | 
| focus | 
| code : PractitionerRole | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-PractitionerRole | 
| min : 1 | 
| max : * | 
| focus | 
| code : Observation | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | 
| min : 0 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : https://fhir.nhs.uk/StructureDefinition/BARSFlag-scene-safety | 
| min : 1 | 
| max : * | 
| focus | 
| code : Flag | 
| profile : http://hl7.org/fhir/StructureDefinition/Flag | 
| min : 0 | 
| max : * | 
| focus | 
| code : Consent | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-Consent | 
| min : 1 | 
| max : * | 
| focus | 
| code : MedicationStatement | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-MedicationStatement | 
| min : 0 | 
| max : * | 
| focus | 
| code : AllergyIntolerance | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-AllergyIntolerance | 
| min : 0 | 
| max : * | 
| focus | 
| code : HealthcareService | 
| profile : https://fhir.hl7.org.uk/StructureDefinition/UKCore-HealthcareService | 
| min : 1 | 
| max : 1 |