# 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

## Data Type Profile: CDA Instance Identifier

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

Identifier datatype profile for representing the source CDA document instance identifier in a FHIR context. The identifier value is expressed as a URN OID (urn:ietf:rfc:3986), with the assigner carrying the PCEHR repository OID and display name.

The purpose of this profile is to provide a consistent Identifier profile for CDA instance identifiers so source document provenance can be carried into FHIR using the mandated URN OID representation and assigner semantics.

Usages:

- Use this DataType Profile: Source CDA Document Identifier

You can also check for usages in the FHIR IG Statistics

### Formal Views of Profile Content

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

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

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Identifier |  | 0..* | Identifier(4.0.1) | An identifier intended for computation
use | ?!Σ | 0..1 | code | usual | official | temp | secondary | old (If known) Binding: IdentifierUse (required): Identifies the purpose for this identifier, if known .
type | Σ | 1..1 | CodeableConcept | Description of identifier Binding: IdentifierTypeVS (26.0.0) (required) Required Pattern: At least the following
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
coding |  | 1..* | Coding | Code defined by a terminology system Fixed Value: (Complex)
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
system |  | 1..1 | uri | Identity of the terminology system Fixed Value: http://digitalhealth.gov.au/fhir/cc/CodeSystem/identifier-type-cs
version |  | 0..1 | string | Version of the system - if relevant
code |  | 1..1 | code | Symbol in syntax defined by the system Fixed Value: CDII
display |  | 1..1 | string | Representation defined by the system Fixed Value: CDA Instance Identifier
userSelected |  | 0..1 | boolean | If this coding was chosen directly by the user
text |  | 0..1 | string | Plain text representation of the concept
system | Σ | 1..1 | uri | The namespace for the identifier value Required Pattern: urn:ietf:rfc:3986
value | Σ | 1..1 | string | The value that is unique Example General: 123456
assigner | Σ | 1..1 | Reference(Organization) | Organization that issued id (may be just text)
identifier | Σ | 1..1 | Identifier | Logical reference, when literal reference is not known
use | ?!Σ | 0..1 | code | usual | official | temp | secondary | old (If known) Binding: IdentifierUse (required): Identifies the purpose for this identifier, if known .
system | Σ | 1..1 | uri | The namespace for the identifier value Required Pattern: urn:ietf:rfc:3986
value | Σ | 1..1 | string | The value that is unique Example General: 123456
display | Σ | 0..1 | string | Text alternative for the resource Required Pattern: PCEHR Assigned Identifier - Repository
Documentation for this format

#### Terminology Bindings

Path | Status | Usage | ValueSet | Version | Source
Identifier.use | Base | required | IdentifierUse | 📍4.0.1 | FHIR Std.
Identifier.type | Base | required | Identifier Type | 📍26.0.0 | This IG
Identifier.assigner.​identifier.use | Base | required | IdentifierUse | 📍4.0.1 | FHIR Std.

#### Constraints

Id | Grade | Path(s) | Description | Expression
ele-1 | error | Identifier, Identifier.use, Identifier.type, Identifier.system, Identifier.value, Identifier.assigner, Identifier.assigner.identifier, Identifier.assigner.identifier.use, Identifier.assigner.identifier.system, Identifier.assigner.identifier.value, Identifier.assigner.display | All FHIR elements must have a @value or children | `hasValue() or (children().count() > id.count())`

This structure is derived from Identifier

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Identifier |  | 0..* | Identifier(4.0.1) | An identifier intended for computation
type |  | 1..1 | CodeableConcept | Description of identifier Binding: IdentifierTypeVS (26.0.0) (required) Required Pattern: At least the following
coding |  | 1..* | Coding | Code defined by a terminology system Fixed Value: (Complex)
system |  | 1..1 | uri | Identity of the terminology system Fixed Value: http://digitalhealth.gov.au/fhir/cc/CodeSystem/identifier-type-cs
code |  | 1..1 | code | Symbol in syntax defined by the system Fixed Value: CDII
display |  | 1..1 | string | Representation defined by the system Fixed Value: CDA Instance Identifier
system |  | 1..1 | uri | The namespace for the identifier value Required Pattern: urn:ietf:rfc:3986
value |  | 1..1 | string | The value that is unique
assigner |  | 1..1 | Reference(Organization) | Organization that issued id (may be just text)
identifier |  | 1..1 | Identifier | Logical reference, when literal reference is not known
system |  | 1..1 | uri | The namespace for the identifier value Required Pattern: urn:ietf:rfc:3986
value |  | 1..1 | string | The value that is unique
display |  | 0..1 | string | Text alternative for the resource Required Pattern: PCEHR Assigned Identifier - Repository
Documentation for this format

#### Terminology Bindings (Differential)

Path | Status | Usage | ValueSet | Version | Source
Identifier.type | Base | required | Identifier Type | 📍26.0.0 | This IG

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Identifier |  | 0..* | Identifier(4.0.1) | An identifier intended for computation
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations Slice: Unordered, Open by value:url Constraints: ext-1
use | ?!Σ | 0..1 | code | usual | official | temp | secondary | old (If known) Binding: IdentifierUse (required): Identifies the purpose for this identifier, if known .
type | Σ | 1..1 | CodeableConcept | Description of identifier Binding: IdentifierTypeVS (26.0.0) (required) Required Pattern: At least the following
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
coding |  | 1..* | Coding | Code defined by a terminology system Fixed Value: (Complex)
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
system |  | 1..1 | uri | Identity of the terminology system Fixed Value: http://digitalhealth.gov.au/fhir/cc/CodeSystem/identifier-type-cs
version |  | 0..1 | string | Version of the system - if relevant
code |  | 1..1 | code | Symbol in syntax defined by the system Fixed Value: CDII
display |  | 1..1 | string | Representation defined by the system Fixed Value: CDA Instance Identifier
userSelected |  | 0..1 | boolean | If this coding was chosen directly by the user
text |  | 0..1 | string | Plain text representation of the concept
system | Σ | 1..1 | uri | The namespace for the identifier value Required Pattern: urn:ietf:rfc:3986
value | Σ | 1..1 | string | The value that is unique Example General: 123456
period | Σ | 0..1 | Period | Time period when id is/was valid for use
assigner | Σ | 1..1 | Reference(Organization) | Organization that issued id (may be just text)
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations Slice: Unordered, Open by value:url Constraints: ext-1
reference | Σ C | 0..1 | string | Literal reference, Relative, internal or absolute URL
type | Σ | 0..1 | uri | Type the reference refers to (e.g. "Patient") Binding: ResourceType (extensible): Aa resource (or, for logical models, the URI of the logical model).
identifier | Σ | 1..1 | Identifier | Logical reference, when literal reference is not known
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations Slice: Unordered, Open by value:url Constraints: ext-1
use | ?!Σ | 0..1 | code | usual | official | temp | secondary | old (If known) Binding: IdentifierUse (required): Identifies the purpose for this identifier, if known .
type | Σ | 0..1 | CodeableConcept | Description of identifier Binding: Identifier Type Codes (extensible): A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.
system | Σ | 1..1 | uri | The namespace for the identifier value Required Pattern: urn:ietf:rfc:3986
value | Σ | 1..1 | string | The value that is unique Example General: 123456
period | Σ | 0..1 | Period | Time period when id is/was valid for use
assigner | Σ | 0..1 | Reference(Organization) | Organization that issued id (may be just text)
display | Σ | 0..1 | string | Text alternative for the resource Required Pattern: PCEHR Assigned Identifier - Repository
Documentation for this format

#### Terminology Bindings

Path | Status | Usage | ValueSet | Version | Source
Identifier.use | Base | required | IdentifierUse | 📍4.0.1 | FHIR Std.
Identifier.type | Base | required | Identifier Type | 📍26.0.0 | This IG
Identifier.assigner.​type | Base | extensible | ResourceType | 📍4.0.1 | FHIR Std.
Identifier.assigner.​identifier.use | Base | required | IdentifierUse | 📍4.0.1 | FHIR Std.
Identifier.assigner.​identifier.type | Base | extensible | IdentifierType | 📍4.0.1 | FHIR Std.

#### Constraints

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

This structure is derived from Identifier

Summary

Mandatory: 7 elements

Key Elements View

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Identifier |  | 0..* | Identifier(4.0.1) | An identifier intended for computation
use | ?!Σ | 0..1 | code | usual | official | temp | secondary | old (If known) Binding: IdentifierUse (required): Identifies the purpose for this identifier, if known .
type | Σ | 1..1 | CodeableConcept | Description of identifier Binding: IdentifierTypeVS (26.0.0) (required) Required Pattern: At least the following
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
coding |  | 1..* | Coding | Code defined by a terminology system Fixed Value: (Complex)
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
system |  | 1..1 | uri | Identity of the terminology system Fixed Value: http://digitalhealth.gov.au/fhir/cc/CodeSystem/identifier-type-cs
version |  | 0..1 | string | Version of the system - if relevant
code |  | 1..1 | code | Symbol in syntax defined by the system Fixed Value: CDII
display |  | 1..1 | string | Representation defined by the system Fixed Value: CDA Instance Identifier
userSelected |  | 0..1 | boolean | If this coding was chosen directly by the user
text |  | 0..1 | string | Plain text representation of the concept
system | Σ | 1..1 | uri | The namespace for the identifier value Required Pattern: urn:ietf:rfc:3986
value | Σ | 1..1 | string | The value that is unique Example General: 123456
assigner | Σ | 1..1 | Reference(Organization) | Organization that issued id (may be just text)
identifier | Σ | 1..1 | Identifier | Logical reference, when literal reference is not known
use | ?!Σ | 0..1 | code | usual | official | temp | secondary | old (If known) Binding: IdentifierUse (required): Identifies the purpose for this identifier, if known .
system | Σ | 1..1 | uri | The namespace for the identifier value Required Pattern: urn:ietf:rfc:3986
value | Σ | 1..1 | string | The value that is unique Example General: 123456
display | Σ | 0..1 | string | Text alternative for the resource Required Pattern: PCEHR Assigned Identifier - Repository
Documentation for this format

#### Terminology Bindings

Path | Status | Usage | ValueSet | Version | Source
Identifier.use | Base | required | IdentifierUse | 📍4.0.1 | FHIR Std.
Identifier.type | Base | required | Identifier Type | 📍26.0.0 | This IG
Identifier.assigner.​identifier.use | Base | required | IdentifierUse | 📍4.0.1 | FHIR Std.

#### Constraints

Id | Grade | Path(s) | Description | Expression
ele-1 | error | Identifier, Identifier.use, Identifier.type, Identifier.system, Identifier.value, Identifier.assigner, Identifier.assigner.identifier, Identifier.assigner.identifier.use, Identifier.assigner.identifier.system, Identifier.assigner.identifier.value, Identifier.assigner.display | All FHIR elements must have a @value or children | `hasValue() or (children().count() > id.count())`

Differential View

This structure is derived from Identifier

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Identifier |  | 0..* | Identifier(4.0.1) | An identifier intended for computation
type |  | 1..1 | CodeableConcept | Description of identifier Binding: IdentifierTypeVS (26.0.0) (required) Required Pattern: At least the following
coding |  | 1..* | Coding | Code defined by a terminology system Fixed Value: (Complex)
system |  | 1..1 | uri | Identity of the terminology system Fixed Value: http://digitalhealth.gov.au/fhir/cc/CodeSystem/identifier-type-cs
code |  | 1..1 | code | Symbol in syntax defined by the system Fixed Value: CDII
display |  | 1..1 | string | Representation defined by the system Fixed Value: CDA Instance Identifier
system |  | 1..1 | uri | The namespace for the identifier value Required Pattern: urn:ietf:rfc:3986
value |  | 1..1 | string | The value that is unique
assigner |  | 1..1 | Reference(Organization) | Organization that issued id (may be just text)
identifier |  | 1..1 | Identifier | Logical reference, when literal reference is not known
system |  | 1..1 | uri | The namespace for the identifier value Required Pattern: urn:ietf:rfc:3986
value |  | 1..1 | string | The value that is unique
display |  | 0..1 | string | Text alternative for the resource Required Pattern: PCEHR Assigned Identifier - Repository
Documentation for this format

#### Terminology Bindings (Differential)

Path | Status | Usage | ValueSet | Version | Source
Identifier.type | Base | required | Identifier Type | 📍26.0.0 | This IG

Snapshot View

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Identifier |  | 0..* | Identifier(4.0.1) | An identifier intended for computation
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations Slice: Unordered, Open by value:url Constraints: ext-1
use | ?!Σ | 0..1 | code | usual | official | temp | secondary | old (If known) Binding: IdentifierUse (required): Identifies the purpose for this identifier, if known .
type | Σ | 1..1 | CodeableConcept | Description of identifier Binding: IdentifierTypeVS (26.0.0) (required) Required Pattern: At least the following
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
coding |  | 1..* | Coding | Code defined by a terminology system Fixed Value: (Complex)
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
system |  | 1..1 | uri | Identity of the terminology system Fixed Value: http://digitalhealth.gov.au/fhir/cc/CodeSystem/identifier-type-cs
version |  | 0..1 | string | Version of the system - if relevant
code |  | 1..1 | code | Symbol in syntax defined by the system Fixed Value: CDII
display |  | 1..1 | string | Representation defined by the system Fixed Value: CDA Instance Identifier
userSelected |  | 0..1 | boolean | If this coding was chosen directly by the user
text |  | 0..1 | string | Plain text representation of the concept
system | Σ | 1..1 | uri | The namespace for the identifier value Required Pattern: urn:ietf:rfc:3986
value | Σ | 1..1 | string | The value that is unique Example General: 123456
period | Σ | 0..1 | Period | Time period when id is/was valid for use
assigner | Σ | 1..1 | Reference(Organization) | Organization that issued id (may be just text)
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations Slice: Unordered, Open by value:url Constraints: ext-1
reference | Σ C | 0..1 | string | Literal reference, Relative, internal or absolute URL
type | Σ | 0..1 | uri | Type the reference refers to (e.g. "Patient") Binding: ResourceType (extensible): Aa resource (or, for logical models, the URI of the logical model).
identifier | Σ | 1..1 | Identifier | Logical reference, when literal reference is not known
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations Slice: Unordered, Open by value:url Constraints: ext-1
use | ?!Σ | 0..1 | code | usual | official | temp | secondary | old (If known) Binding: IdentifierUse (required): Identifies the purpose for this identifier, if known .
type | Σ | 0..1 | CodeableConcept | Description of identifier Binding: Identifier Type Codes (extensible): A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.
system | Σ | 1..1 | uri | The namespace for the identifier value Required Pattern: urn:ietf:rfc:3986
value | Σ | 1..1 | string | The value that is unique Example General: 123456
period | Σ | 0..1 | Period | Time period when id is/was valid for use
assigner | Σ | 0..1 | Reference(Organization) | Organization that issued id (may be just text)
display | Σ | 0..1 | string | Text alternative for the resource Required Pattern: PCEHR Assigned Identifier - Repository
Documentation for this format

#### Terminology Bindings

Path | Status | Usage | ValueSet | Version | Source
Identifier.use | Base | required | IdentifierUse | 📍4.0.1 | FHIR Std.
Identifier.type | Base | required | Identifier Type | 📍26.0.0 | This IG
Identifier.assigner.​type | Base | extensible | ResourceType | 📍4.0.1 | FHIR Std.
Identifier.assigner.​identifier.use | Base | required | IdentifierUse | 📍4.0.1 | FHIR Std.
Identifier.assigner.​identifier.type | Base | extensible | IdentifierType | 📍4.0.1 | FHIR Std.

#### Constraints

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

This structure is derived from Identifier

Summary

Mandatory: 7 elements

Other representations of profile: CSV, Excel, Schematron