FHIR Extensions Pack
5.3.0-ballot-tc1 - (September 2025 Ballot) International flag

FHIR Extensions Pack, published by HL7 International / FHIR Infrastructure. This guide is not an authorized publication; it is the continuous build for version 5.3.0-ballot-tc1 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/fhir-extensions/ and changes regularly. See the Directory of published versions

Extension: ValueSet Supplement

Official URL: http://hl7.org/fhir/StructureDefinition/valueset-supplement Version: 5.3.0-ballot-tc1
Standards status: Trial-use Maturity Level: 3 Responsible: HL7 International / Terminology Infrastructure Computable Name: VSSupplement
Other Identifiers: OID:2.16.840.1.113883.4.642.5.1221

This extension declares that a value set depends on a particular CodeSystem supplement and should not be used in its absence.

Context of Use

This extension may be used on the following element(s)

The extension valueset-supplement is a little bit ambiguous when used on the base of ValueSet. The ambiguity arises in two contexts:

  1. Validating a code. When a server is validating a code against a value set with codes from two different systems, and the value set declares a dependency on a supplement it doesn't have, the server cannot be sure whether it is for the code system the code is in, or a different one. If the supplement is for a different code system, the server could safely ignore it, but it can't know
  2. A similar situation arises when a ValueSet depends on different versions of a code system, which is valid and also a feature used in production value sets. That is, ValueSet.compose.include references different versions of the same code system. In this situation, it's ambiguous which version is being supplemented, or needs to be, and it might not be all of them.

For both these reasons, the preferred location for supplement dependency is on ValueSet.compose.include or ValueSet.compose.exclude as appropriate: this makes it clear which code system is being supplemented.

Usage info

Usages:

You can also check for usages in the FHIR IG Statistics

Changes since version 5.2.0:

  • No changes

    • Formal Views of Extension Content

    Description of Profiles, Differentials, Snapshots, and how the XML and JSON presentations work.

    This structure is derived from Extension

    Summary

    Simple Extension with the type canonical: This extension declares that a value set depends on a particular CodeSystem supplement and should not be used in its absence.

    Maturity: 3

    This structure is derived from Extension

    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. Extension 0..* Extension Declares dependency on a particular supplment
    ... extension 0..0
    ... url 1..1 uri "http://hl7.org/fhir/StructureDefinition/valueset-supplement"
    ... value[x] 1..1 canonical(CodeSystem) Value of extension

    doco Documentation for this format
    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. Extension 0..* Extension Declares dependency on a particular supplment
    ... id 0..1 id Unique id for inter-element referencing
    ... extension 0..0
    ... url 1..1 uri "http://hl7.org/fhir/StructureDefinition/valueset-supplement"

    doco Documentation for this format

    This structure is derived from Extension

    Summary

    Simple Extension with the type canonical: This extension declares that a value set depends on a particular CodeSystem supplement and should not be used in its absence.

    Maturity: 3

    Differential View

    This structure is derived from Extension

    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. Extension 0..* Extension Declares dependency on a particular supplment
    ... extension 0..0
    ... url 1..1 uri "http://hl7.org/fhir/StructureDefinition/valueset-supplement"
    ... value[x] 1..1 canonical(CodeSystem) Value of extension

    doco Documentation for this format

    Snapshot View

    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. Extension 0..* Extension Declares dependency on a particular supplment
    ... id 0..1 id Unique id for inter-element referencing
    ... extension 0..0
    ... url 1..1 uri "http://hl7.org/fhir/StructureDefinition/valueset-supplement"

    doco Documentation for this format

     

    Other representations of profile: CSV, Excel, Schematron

    Constraints

    IdGradePath(s)DetailsRequirements
    ele-1error**ALL** elementsAll FHIR elements must have a @value or children
    : hasValue() or (children().count() > id.count())
    ext-1error**ALL** extensionsMust have either extensions or value[x], not both
    : extension.exists() != value.exists()

    R4B

    The extension is not used in R4B

    • Duplicate Resource http://hl7.org/fhir/StructureDefinition/valueset-supplement of type StructureDefinition (existing version 4.3.0, new version 5.3.0-ballot-tc1)

    R4

    The extension is not used in R4

    • Duplicate Resource http://hl7.org/fhir/StructureDefinition/valueset-supplement of type StructureDefinition (existing version 4.0.1, new version 5.3.0-ballot-tc1)

    R3

    The extension is represented a little differently in R3:

    • Map the type canonical to uri on the element Extension.value[x]
    • Note: Extensions that have been modified for R3 are still draft while real-world experience is collected
    Name Flags Card. Type Description & Constraints      Filter: Filters doco
    . . Extension 0..* Extension Declares dependency on a particular supplment
    . . . extension 0 .. 0
    . . . url 1 .. 1 uri "http://hl7.org/fhir/StructureDefinition/valueset-supplement"
    . . . value[x] 1.. 1 uri Value of extension

    doco Documentation for this format

    Search Parameters for this Extension

    (none found)