Consolidated CDA (C-CDA)
4.0.0 - STU4 United States of America flag

Consolidated CDA (C-CDA), published by Health Level Seven. This guide is not an authorized publication; it is the continuous build for version 4.0.0 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/CDA-ccda/ and changes regularly. See the Directory of published versions

Logical Model: External Document Reference

Official URL: http://hl7.org/cda/us/ccda/StructureDefinition/ExternalDocumentReference Version: 4.0.0
Draft as of 2025-10-02 Computable Name: ExternalDocumentReference
Other Identifiers: urn:ietf:rfc:3986#Uniform Resource Identifier (URI)#urn:hl7ii:2.16.840.1.113883.10.20.22.4.115:2014-06-09

Where it is necessary to reference an external clinical document, the External Document Reference template can be used to reference this external document. However, if the containing document is appending to or replacing another document in the same set, that relationship is set in the header, using ClinicalDocument/relatedDocument.

Usages:

You can also check for usages in the FHIR IG Statistics

Changes since version 3.0.0:

  • New Content

    • Formal Views of Template Content

    Description of Template, Differentials, Snapshots and how the different presentations work.

    This structure is derived from ExternalDocument

    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. ExternalDocument C 1..1 ExternalDocument XML Namespace: urn:hl7-org:v3
    Base for all types and resources
    Instance of this type are validated by templateId
    Logical Container: ClinicalDocument (CDA Class)
    Constraints: should-setId, should-versionNumber
    ... Slices for templateId 1..* II Slice: Unordered, Open by value:root, value:extension
    .... templateId:external-doc-ref 1..1 II
    ..... @root 1..1 oid, uuid, ruid Required Pattern: 2.16.840.1.113883.10.20.22.4.115
    ..... @extension 1..1 st Required Pattern: 2014-06-09
    ... @classCode 1..1 cs Fixed Value: DOCCLIN
    ... @moodCode 1..1 cs
    ... code 1..1 CD
    ... setId 0..1 II
    ... versionNumber 0..1 INT

    doco Documentation for this format

    Constraints

    Id Grade Path(s) Description Expression
    should-setId warning ExternalDocument SHOULD contain setId setId.exists()
    should-versionNumber warning ExternalDocument SHOULD contain versionNumber versionNumber.exists()
    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. ExternalDocument C 1..1 ExternalDocument XML Namespace: urn:hl7-org:v3
    Base for all types and resources
    Instance of this type are validated by templateId
    Logical Container: ClinicalDocument (CDA Class)
    Constraints: should-setId, should-versionNumber
    ... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
    ... realmCode 0..* CS
    ... typeId C 0..1 II Constraints: II-1
    .... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
    .... @assigningAuthorityName 0..1 st
    .... @displayable 0..1 bl
    .... @root 1..1 oid, uuid, ruid Fixed Value: 2.16.840.1.113883.1.3
    .... @extension 1..1 st
    .... templateId:external-doc-ref 1..1 II
    ..... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
    ..... @assigningAuthorityName 0..1 st
    ..... @displayable 0..1 bl
    ..... @root 1..1 oid, uuid, ruid Required Pattern: 2.16.840.1.113883.10.20.22.4.115
    ..... @extension 1..1 st Required Pattern: 2014-06-09
    ... @classCode 1..1 cs Binding: ActClassDocument (required)
    Fixed Value: DOCCLIN
    ... @moodCode 1..1 cs Binding: CDAActMood (required)
    Fixed Value: EVN
    ... id 1..1 II
    ... code 1..1 CD Binding: FHIRDocumentTypeCodes (example)
    ... text 0..1 ED
    ... setId 0..1 II
    ... versionNumber 0..1 INT
    ... sdtcAuthor 0..* Author XML Namespace: urn:hl7-org:sdtc
    XML: author (urn:hl7-org:sdtc)

    doco Documentation for this format

    Terminology Bindings

    Path Status Usage ValueSet Version Source
    ExternalDocument.nullFlavor Base required CDANullFlavor 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.typeId.​nullFlavor Base required CDANullFlavor 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.templateId:external-doc-ref.​nullFlavor Base required CDANullFlavor 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.classCode Base required ActClassDocument 📦3.0.0 THO v6.5
    ExternalDocument.moodCode Base required CDAActMood 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.code Base example FHIR Document Type Codes 📦5.0.0 FHIR Std.

    Constraints

    Id Grade Path(s) Description Expression
    II-1 error ExternalDocument.typeId An II instance must have either a root or an nullFlavor. root.exists() or nullFlavor.exists()
    should-setId warning ExternalDocument SHOULD contain setId setId.exists()
    should-versionNumber warning ExternalDocument SHOULD contain versionNumber versionNumber.exists()
    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. ExternalDocument C 1..1 ExternalDocument XML Namespace: urn:hl7-org:v3
    Base for all types and resources
    Instance of this type are validated by templateId
    Logical Container: ClinicalDocument (CDA Class)
    Constraints: should-setId, should-versionNumber
    ... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
    ... realmCode 0..* CS
    ... typeId C 0..1 II Constraints: II-1
    .... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
    .... @assigningAuthorityName 0..1 st
    .... @displayable 0..1 bl
    .... @root 1..1 oid, uuid, ruid Fixed Value: 2.16.840.1.113883.1.3
    .... @extension 1..1 st
    .... templateId:external-doc-ref 1..1 II
    ..... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
    ..... @assigningAuthorityName 0..1 st
    ..... @displayable 0..1 bl
    ..... @root 1..1 oid, uuid, ruid Required Pattern: 2.16.840.1.113883.10.20.22.4.115
    ..... @extension 1..1 st Required Pattern: 2014-06-09
    ... @classCode 1..1 cs Binding: ActClassDocument (required)
    Fixed Value: DOCCLIN
    ... @moodCode 1..1 cs Binding: CDAActMood (required)
    Fixed Value: EVN
    ... id 1..1 II
    ... code 1..1 CD Binding: FHIRDocumentTypeCodes (example)
    ... text 0..1 ED
    ... setId 0..1 II
    ... versionNumber 0..1 INT
    ... sdtcAuthor 0..* Author XML Namespace: urn:hl7-org:sdtc
    XML: author (urn:hl7-org:sdtc)

    doco Documentation for this format

    Terminology Bindings

    Path Status Usage ValueSet Version Source
    ExternalDocument.nullFlavor Base required CDANullFlavor 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.typeId.​nullFlavor Base required CDANullFlavor 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.templateId:external-doc-ref.​nullFlavor Base required CDANullFlavor 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.classCode Base required ActClassDocument 📦3.0.0 THO v6.5
    ExternalDocument.moodCode Base required CDAActMood 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.code Base example FHIR Document Type Codes 📦5.0.0 FHIR Std.

    Constraints

    Id Grade Path(s) Description Expression
    II-1 error ExternalDocument.typeId An II instance must have either a root or an nullFlavor. root.exists() or nullFlavor.exists()
    should-setId warning ExternalDocument SHOULD contain setId setId.exists()
    should-versionNumber warning ExternalDocument SHOULD contain versionNumber versionNumber.exists()

    This structure is derived from ExternalDocument

    Summary

    Mandatory: 8 elements
    Fixed: 1 element

    Slices

    This structure defines the following Slices:

    • The element 2 is sliced based on the values of ExternalDocument.templateId

    Differential View

    This structure is derived from ExternalDocument

    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. ExternalDocument C 1..1 ExternalDocument XML Namespace: urn:hl7-org:v3
    Base for all types and resources
    Instance of this type are validated by templateId
    Logical Container: ClinicalDocument (CDA Class)
    Constraints: should-setId, should-versionNumber
    ... Slices for templateId 1..* II Slice: Unordered, Open by value:root, value:extension
    .... templateId:external-doc-ref 1..1 II
    ..... @root 1..1 oid, uuid, ruid Required Pattern: 2.16.840.1.113883.10.20.22.4.115
    ..... @extension 1..1 st Required Pattern: 2014-06-09
    ... @classCode 1..1 cs Fixed Value: DOCCLIN
    ... @moodCode 1..1 cs
    ... code 1..1 CD
    ... setId 0..1 II
    ... versionNumber 0..1 INT

    doco Documentation for this format

    Constraints

    Id Grade Path(s) Description Expression
    should-setId warning ExternalDocument SHOULD contain setId setId.exists()
    should-versionNumber warning ExternalDocument SHOULD contain versionNumber versionNumber.exists()

    Key Elements View

    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. ExternalDocument C 1..1 ExternalDocument XML Namespace: urn:hl7-org:v3
    Base for all types and resources
    Instance of this type are validated by templateId
    Logical Container: ClinicalDocument (CDA Class)
    Constraints: should-setId, should-versionNumber
    ... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
    ... realmCode 0..* CS
    ... typeId C 0..1 II Constraints: II-1
    .... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
    .... @assigningAuthorityName 0..1 st
    .... @displayable 0..1 bl
    .... @root 1..1 oid, uuid, ruid Fixed Value: 2.16.840.1.113883.1.3
    .... @extension 1..1 st
    .... templateId:external-doc-ref 1..1 II
    ..... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
    ..... @assigningAuthorityName 0..1 st
    ..... @displayable 0..1 bl
    ..... @root 1..1 oid, uuid, ruid Required Pattern: 2.16.840.1.113883.10.20.22.4.115
    ..... @extension 1..1 st Required Pattern: 2014-06-09
    ... @classCode 1..1 cs Binding: ActClassDocument (required)
    Fixed Value: DOCCLIN
    ... @moodCode 1..1 cs Binding: CDAActMood (required)
    Fixed Value: EVN
    ... id 1..1 II
    ... code 1..1 CD Binding: FHIRDocumentTypeCodes (example)
    ... text 0..1 ED
    ... setId 0..1 II
    ... versionNumber 0..1 INT
    ... sdtcAuthor 0..* Author XML Namespace: urn:hl7-org:sdtc
    XML: author (urn:hl7-org:sdtc)

    doco Documentation for this format

    Terminology Bindings

    Path Status Usage ValueSet Version Source
    ExternalDocument.nullFlavor Base required CDANullFlavor 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.typeId.​nullFlavor Base required CDANullFlavor 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.templateId:external-doc-ref.​nullFlavor Base required CDANullFlavor 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.classCode Base required ActClassDocument 📦3.0.0 THO v6.5
    ExternalDocument.moodCode Base required CDAActMood 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.code Base example FHIR Document Type Codes 📦5.0.0 FHIR Std.

    Constraints

    Id Grade Path(s) Description Expression
    II-1 error ExternalDocument.typeId An II instance must have either a root or an nullFlavor. root.exists() or nullFlavor.exists()
    should-setId warning ExternalDocument SHOULD contain setId setId.exists()
    should-versionNumber warning ExternalDocument SHOULD contain versionNumber versionNumber.exists()

    Snapshot View

    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. ExternalDocument C 1..1 ExternalDocument XML Namespace: urn:hl7-org:v3
    Base for all types and resources
    Instance of this type are validated by templateId
    Logical Container: ClinicalDocument (CDA Class)
    Constraints: should-setId, should-versionNumber
    ... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
    ... realmCode 0..* CS
    ... typeId C 0..1 II Constraints: II-1
    .... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
    .... @assigningAuthorityName 0..1 st
    .... @displayable 0..1 bl
    .... @root 1..1 oid, uuid, ruid Fixed Value: 2.16.840.1.113883.1.3
    .... @extension 1..1 st
    .... templateId:external-doc-ref 1..1 II
    ..... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
    ..... @assigningAuthorityName 0..1 st
    ..... @displayable 0..1 bl
    ..... @root 1..1 oid, uuid, ruid Required Pattern: 2.16.840.1.113883.10.20.22.4.115
    ..... @extension 1..1 st Required Pattern: 2014-06-09
    ... @classCode 1..1 cs Binding: ActClassDocument (required)
    Fixed Value: DOCCLIN
    ... @moodCode 1..1 cs Binding: CDAActMood (required)
    Fixed Value: EVN
    ... id 1..1 II
    ... code 1..1 CD Binding: FHIRDocumentTypeCodes (example)
    ... text 0..1 ED
    ... setId 0..1 II
    ... versionNumber 0..1 INT
    ... sdtcAuthor 0..* Author XML Namespace: urn:hl7-org:sdtc
    XML: author (urn:hl7-org:sdtc)

    doco Documentation for this format

    Terminology Bindings

    Path Status Usage ValueSet Version Source
    ExternalDocument.nullFlavor Base required CDANullFlavor 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.typeId.​nullFlavor Base required CDANullFlavor 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.templateId:external-doc-ref.​nullFlavor Base required CDANullFlavor 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.classCode Base required ActClassDocument 📦3.0.0 THO v6.5
    ExternalDocument.moodCode Base required CDAActMood 📦2.0.1-sd Clinical Document Architecture v2.0
    ExternalDocument.code Base example FHIR Document Type Codes 📦5.0.0 FHIR Std.

    Constraints

    Id Grade Path(s) Description Expression
    II-1 error ExternalDocument.typeId An II instance must have either a root or an nullFlavor. root.exists() or nullFlavor.exists()
    should-setId warning ExternalDocument SHOULD contain setId setId.exists()
    should-versionNumber warning ExternalDocument SHOULD contain versionNumber versionNumber.exists()

    This structure is derived from ExternalDocument

    Summary

    Mandatory: 8 elements
    Fixed: 1 element

    Slices

    This structure defines the following Slices:

    • The element 2 is sliced based on the values of ExternalDocument.templateId

     

    Other representations of profile: CSV, Excel