# Common Components FHIR Implementation Guide

26.0.0 - Trial

Common Components FHIR Implementation Guide, published by Australian Digital Health Agency. This guide is not an authorized publication; it is the continuous build for version 26.0.0 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/AuDigitalHealth/common-components/ and changes regularly. See the Directory of published versions

## Extension: Source CDA Document Identifier

Official URL: http://digitalhealth.gov.au/fhir/cc/StructureDefinition/source-cda-document-identifier | Version: 26.0.0
Draft as of 2026-07-14 | Computable Name: Source_CDA_Document_Identifier
Copyright/Legal: This content is licensed under a Creative Commons Attribution 4.0 International License. See https://creativecommons.org/licenses/by/4.0/

The instance identifier of the source CDA clinical document from which this FHIR resource was derived. Carries the `/ClinicalDocument/id` value to preserve source document provenance in a FHIR context.

The purpose of this extension is to record the source CDA document instance identifier on FHIR resources derived from CDA, enabling traceability back to the originating clinical document without conflating provenance with the resource's own business identifiers.

Context of Use

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

- Element ID: `MedicationDispense`
- Element ID: `MedicationRequest`

Usage info

Usages:

- Examples for this Extension: MedicationDispense/medicationdispense-cda-extensions-example, MedicationDispense/medicationdispense-repeat-progression-example-1, MedicationDispense/medicationdispense-repeat-progression-example-2, MedicationDispense/medicationdispense-repeat-progression-example-3... Show 4 more, MedicationDispense/medicationdispense-repeat-progression-example-4, MedicationDispense/medicationdispense-repeat-progression-example-5, MedicationDispense/medicationdispense-repeat-progression-example-6 and MedicationRequest/medicationrequest-cda-extensions-example

You can also check for usages in the FHIR IG Statistics

### Formal Views of Extension Content

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

- Differential Table
- Snapshot Table
- Statistics/References
- All

This structure is derived from Extension

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Extension |  | 0..* | Extension(4.0.1) | Source CDA Document Identifier
extension |  | 0..0 |  | Extension
url |  | 1..1 | uri | "http://digitalhealth.gov.au/fhir/cc/StructureDefinition/source-cda-document-identifier"
value[x] |  | 0..1 | CDA_Instance_Identifier(26.0.0) | Source CDA document identifier
Documentation for this format

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Extension |  | 0..* | Extension(4.0.1) | Source CDA Document Identifier Constraints: ext-1
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..0 |  | Extension Slice: Unordered, Open by value:url Constraints: ext-1
url |  | 1..1 | uri | "http://digitalhealth.gov.au/fhir/cc/StructureDefinition/source-cda-document-identifier"
value[x] |  | 0..1 | CDA_Instance_Identifier(26.0.0) | Source CDA document identifier
Documentation for this format

This structure is derived from Extension

Summary

Simple Extension with the type Identifier: The instance identifier of the source CDA clinical document from which this FHIR resource was derived. Carries the `/ClinicalDocument/id` value to preserve source document provenance in a FHIR context.

Differential View

This structure is derived from Extension

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Extension |  | 0..* | Extension(4.0.1) | Source CDA Document Identifier
extension |  | 0..0 |  | Extension
url |  | 1..1 | uri | "http://digitalhealth.gov.au/fhir/cc/StructureDefinition/source-cda-document-identifier"
value[x] |  | 0..1 | CDA_Instance_Identifier(26.0.0) | Source CDA document identifier
Documentation for this format

Snapshot View

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Extension |  | 0..* | Extension(4.0.1) | Source CDA Document Identifier Constraints: ext-1
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..0 |  | Extension Slice: Unordered, Open by value:url Constraints: ext-1
url |  | 1..1 | uri | "http://digitalhealth.gov.au/fhir/cc/StructureDefinition/source-cda-document-identifier"
value[x] |  | 0..1 | CDA_Instance_Identifier(26.0.0) | Source CDA document identifier
Documentation for this format

This structure is derived from Extension

Summary

Simple Extension with the type Identifier: The instance identifier of the source CDA clinical document from which this FHIR resource was derived. Carries the `/ClinicalDocument/id` value to preserve source document provenance in a FHIR context.

Other representations of profile: CSV, Excel, Schematron

#### Constraints

Id | Grade | Path(s) | Description | Expression
ele-1 | error | Extension, Extension.value[x] | All FHIR elements must have a @value or children | `hasValue() or (children().count() > id.count())`
ext-1 | error | Extension | Must have either extensions or value[x], not both | `extension.exists() != value.exists()`