Release 5

This page is part of the FHIR Specification (v5.0.0: R5 - STU). This is the current published version in it's permanent home (it will always be available at this URL). For a full list of available versions, see the Directory of published versions . Page versions: R5 R4B R4 R3

8.21 Resource Linkage - Content

Patient Care icon

Work Group

Maturity Level: 0

Trial Use

Security Category: Patient

Compartments: Practitioner

Identifies two or more records (resource instances) that refer to the same real-world "occurrence".

8.21.1 Scope and Usage

This resource allows the assertion of linkages between multiple resource instances (generally of the same type) that are referring to the same underlying business objects. For example, multiple Condition records that refer to the same underlying problem/issue for a Patient; multiple AllergyIntolerance records that refer to the same reaction susceptibility; multiple Patient, Practitioner and/or RelatedPerson records that refer to the same human being or animal.

FHIR supports a process for sharing electronic records. It is common for multiple records to exist that deal with the same real-world phenomenon. This can result from information being captured by different systems, information being captured within a single system by different users (either deliberately to represent distinct perspectives or accidentally when a new record is created rather than updating an existing record). These multiple records may be referred to as "duplicate" records, but in practice they aren't often actually "duplicate" in that the data represented (and the history of the records) will be at least somewhat distinct.

In some cases, the solution after identifying duplicates is to deprecate one of the records (e.g. by changing the status to "Entered in Error") and to move all relevant information to the surviving record. In other cases, the resource may support the ability to establish a linkage directly between the resources. However, in some cases, both records may need to survive or there might be a desire to have both resources continue to be maintained, perhaps because the resources live on different servers or have different 'owners'. The Linkage resource is intended to satisfy this use-case.

8.21.2 Boundaries and Relationships

The Person resource should be used to link a person independent of a specific health-related context. Linkage can be used for all other use cases.

8.21.3 References to this Resource

No references for this Resource.

Structure

Name	Flags	Card.	Type	Description & Constraints
Linkage	TU		DomainResource	Links records for 'same' item + Rule: Must have at least two items Elements defined in Ancestors: id, meta, implicitRules, language, text, contained, extension, modifierExtension
active	Σ	0..1	boolean	Whether this linkage assertion is active or not
author	Σ	0..1	Reference(Practitioner \| PractitionerRole \| Organization)	Who is responsible for linkages
item	Σ C	1..*	BackboneElement	Item to be linked
type	Σ	1..1	code	source \| alternate \| historical Binding: Linkage Type (Required)
resource	Σ	1..1	Reference(Any)	Resource being linked
Documentation for this format

See the Extensions for this resource

UML Diagram (Legend)

XML Template

<Linkage xmlns="http://hl7.org/fhir"> 
 <!-- from Resource: id, meta, implicitRules, and language -->
 <!-- from DomainResource: text, contained, extension, and modifierExtension -->
 <active value="[boolean]"/><!-- 0..1 Whether this linkage assertion is active or not -->
 <author><!-- 0..1 Reference(Organization|Practitioner|PractitionerRole) Who is responsible for linkages --></author>
 <item>  <!-- I 1..* Item to be linked -->
  <type value="[code]"/><!-- 1..1 source | alternate | historical -->
  <resource><!-- 1..1 Reference(Any) Resource being linked --></resource>
 </item>
</Linkage>

JSON Template

{
  "resourceType" : "Linkage",
  // from Resource: id, meta, implicitRules, and language
  // from DomainResource: text, contained, extension, and modifierExtension
  "active" : <boolean>, // Whether this linkage assertion is active or not
  "author" : { Reference(Organization|Practitioner|PractitionerRole) }, // Who is responsible for linkages
  "item" : [{ // I R!  Item to be linked
    "type" : "<code>", // R!  source | alternate | historical
    "resource" : { Reference(Any) } // R!  Resource being linked
  }]
}

Turtle Template

@prefix fhir: <http://hl7.org/fhir/> .


[ a fhir:Linkage;
  fhir:nodeRole fhir:treeRoot; # if this is the parser root

  # from Resource: .id, .meta, .implicitRules, and .language
  # from DomainResource: .text, .contained, .extension, and .modifierExtension
  fhir:active [ boolean ] ; # 0..1 Whether this linkage assertion is active or not
  fhir:author [ Reference(Organization|Practitioner|PractitionerRole) ] ; # 0..1 Who is responsible for linkages
  fhir:item ( [ # 1..* I Item to be linked
    fhir:type [ code ] ; # 1..1 source | alternate | historical
    fhir:resource [ Reference(Any) ] ; # 1..1 Resource being linked
  ] ... ) ;
]

Changes from both R4 and R4B

Linkage

No Changes

See the Full Difference for further information

This analysis is available for R4 as XML or JSON and for R4B as XML or JSON.

See R4 <--> R5 Conversion Maps (status = See Conversions Summary.)

Structure

Name	Flags	Card.	Type	Description & Constraints
Linkage	TU		DomainResource	Links records for 'same' item + Rule: Must have at least two items Elements defined in Ancestors: id, meta, implicitRules, language, text, contained, extension, modifierExtension
active	Σ	0..1	boolean	Whether this linkage assertion is active or not
author	Σ	0..1	Reference(Practitioner \| PractitionerRole \| Organization)	Who is responsible for linkages
item	Σ C	1..*	BackboneElement	Item to be linked
type	Σ	1..1	code	source \| alternate \| historical Binding: Linkage Type (Required)
resource	Σ	1..1	Reference(Any)	Resource being linked
Documentation for this format

See the Extensions for this resource

UML Diagram (Legend)

XML Template

<Linkage xmlns="http://hl7.org/fhir"> 
 <!-- from Resource: id, meta, implicitRules, and language -->
 <!-- from DomainResource: text, contained, extension, and modifierExtension -->
 <active value="[boolean]"/><!-- 0..1 Whether this linkage assertion is active or not -->
 <author><!-- 0..1 Reference(Organization|Practitioner|PractitionerRole) Who is responsible for linkages --></author>
 <item>  <!-- I 1..* Item to be linked -->
  <type value="[code]"/><!-- 1..1 source | alternate | historical -->
  <resource><!-- 1..1 Reference(Any) Resource being linked --></resource>
 </item>
</Linkage>

JSON Template

{
  "resourceType" : "Linkage",
  // from Resource: id, meta, implicitRules, and language
  // from DomainResource: text, contained, extension, and modifierExtension
  "active" : <boolean>, // Whether this linkage assertion is active or not
  "author" : { Reference(Organization|Practitioner|PractitionerRole) }, // Who is responsible for linkages
  "item" : [{ // I R!  Item to be linked
    "type" : "<code>", // R!  source | alternate | historical
    "resource" : { Reference(Any) } // R!  Resource being linked
  }]
}

Turtle Template

@prefix fhir: <http://hl7.org/fhir/> .


[ a fhir:Linkage;
  fhir:nodeRole fhir:treeRoot; # if this is the parser root

  # from Resource: .id, .meta, .implicitRules, and .language
  # from DomainResource: .text, .contained, .extension, and .modifierExtension
  fhir:active [ boolean ] ; # 0..1 Whether this linkage assertion is active or not
  fhir:author [ Reference(Organization|Practitioner|PractitionerRole) ] ; # 0..1 Who is responsible for linkages
  fhir:item ( [ # 1..* I Item to be linked
    fhir:type [ code ] ; # 1..1 source | alternate | historical
    fhir:resource [ Reference(Any) ] ; # 1..1 Resource being linked
  ] ... ) ;
]

Changes from both R4 and R4B

Linkage

No Changes

See the Full Difference for further information

This analysis is available for R4 as XML or JSON and for R4B as XML or JSON.

See R4 <--> R5 Conversion Maps (status = See Conversions Summary.)

Additional definitions: Master Definition XML + JSON, XML Schema/Schematron + JSON Schema, ShEx (for Turtle) + see the extensions, the spreadsheet version & the dependency analysis

This resource has liquid template to serve as an exemplar for best practice presention to humans.

8.21.4.1 Terminology Bindings

Path	ValueSet	Type	Documentation
Linkage.item.type	LinkageType	Required	Used to distinguish different roles a resource can play within a set of linked resources.

Path

ValueSet

Type

Documentation

Linkage.item.type

LinkageType

Required

Used to distinguish different roles a resource can play within a set of linked resources.

8.21.4.2 Constraints

UniqueKey

Level

Location

Description

Expression

lnk-1

Rule

(base)

Must have at least two items

item.count()>1

8.21.5 Search Parameters

Search parameters for this resource. See also the full list of search parameters for this resource, and check the Extensions registry for search parameters on extensions related to this resource. The common parameters also apply. See Searching for more information about searching in REST, messaging, and services.

Name	Type	Description	Expression	In Common
author	reference	Author of the Linkage	Linkage.author (Practitioner, Organization, PractitionerRole)
item	reference	Matches on any item in the Linkage	Linkage.item.resource (Any)
source	reference	Matches on any item in the Linkage with a type of 'source'	Linkage.item.resource (Any)