Clinical Document Architecture with Australian Schema, published by Australian Digital Health Agency. This guide is not an authorized publication; it is the continuous build for version 1.0.1 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/AuDigitalHealth/cda-au-schema/ and changes regularly. See the Directory of published versions

Logical Model: ST: CharacterString (V3 Data Type)

Official URL: http://hl7.org/cda/stds/core/StructureDefinition/ST Version: 1.0.1
Active as of 2025-10-09 Maturity Level: 1 Responsible: HL7 Computable Name: ST

The character string data type stands for text data, primarily intended for machine processing (e.g., sorting, querying, indexing, etc.) Used for names, symbols, and formal expressions.

Usages:

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.

NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
.. ST C 1..* ANY XML Namespace: urn:hl7-org:v3
Base for all types and resources

Elements defined in Ancestors:@nullFlavor
Logical Container: ClinicalDocument (CDA Class)
Constraints: text-null
... (Choice of one) 1..1
.... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
.... xmlText 0..1 st Allows for mixed text content
... @representation 0..1 cs Fixed Value: TXT
... @mediaType 0..1 cs Fixed Value: text/plain

doco Documentation for this format

Terminology Bindings

Path Status Usage ValueSet Version Source
ST.nullFlavor Base required CDANullFlavor 📦1.0.1 This IG

Constraints

Id Grade Path(s) Description Expression
text-null error ST xmlText and nullFlavor are mutually exclusive (one must be present) (xmlText | nullFlavor).count() = 1

This structure is derived from ANY

NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
.. ST C 1..* ANY XML Namespace: urn:hl7-org:v3
Base for all types and resources

Elements defined in Ancestors:@nullFlavor
Logical Container: ClinicalDocument (CDA Class)
Constraints: text-null
... @representation 0..1 cs Fixed Value: TXT
... @mediaType 0..1 cs Fixed Value: text/plain
... @language 0..1 cs

doco Documentation for this format

Constraints

Id Grade Path(s) Description Expression
text-null error ST xmlText and nullFlavor are mutually exclusive (one must be present) (xmlText | nullFlavor).count() = 1
NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
.. ST C 1..* ANY XML Namespace: urn:hl7-org:v3
Base for all types and resources

Elements defined in Ancestors:@nullFlavor
Logical Container: ClinicalDocument (CDA Class)
Constraints: text-null
... (Choice of one) 1..1
.... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
.... xmlText 0..1 st Allows for mixed text content
... @representation 0..1 cs Fixed Value: TXT
... @mediaType 0..1 cs Fixed Value: text/plain

doco Documentation for this format

Terminology Bindings

Path Status Usage ValueSet Version Source
ST.nullFlavor Base required CDANullFlavor 📦1.0.1 This IG

Constraints

Id Grade Path(s) Description Expression
text-null error ST xmlText and nullFlavor are mutually exclusive (one must be present) (xmlText | nullFlavor).count() = 1

This structure is derived from ANY

Key Elements View

NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
.. ST C 1..* ANY XML Namespace: urn:hl7-org:v3
Base for all types and resources

Elements defined in Ancestors:@nullFlavor
Logical Container: ClinicalDocument (CDA Class)
Constraints: text-null
... (Choice of one) 1..1
.... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
.... xmlText 0..1 st Allows for mixed text content
... @representation 0..1 cs Fixed Value: TXT
... @mediaType 0..1 cs Fixed Value: text/plain

doco Documentation for this format

Terminology Bindings

Path Status Usage ValueSet Version Source
ST.nullFlavor Base required CDANullFlavor 📦1.0.1 This IG

Constraints

Id Grade Path(s) Description Expression
text-null error ST xmlText and nullFlavor are mutually exclusive (one must be present) (xmlText | nullFlavor).count() = 1

Differential View

This structure is derived from ANY

NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
.. ST C 1..* ANY XML Namespace: urn:hl7-org:v3
Base for all types and resources

Elements defined in Ancestors:@nullFlavor
Logical Container: ClinicalDocument (CDA Class)
Constraints: text-null
... @representation 0..1 cs Fixed Value: TXT
... @mediaType 0..1 cs Fixed Value: text/plain
... @language 0..1 cs

doco Documentation for this format

Constraints

Id Grade Path(s) Description Expression
text-null error ST xmlText and nullFlavor are mutually exclusive (one must be present) (xmlText | nullFlavor).count() = 1

Snapshot View

NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
.. ST C 1..* ANY XML Namespace: urn:hl7-org:v3
Base for all types and resources

Elements defined in Ancestors:@nullFlavor
Logical Container: ClinicalDocument (CDA Class)
Constraints: text-null
... (Choice of one) 1..1
.... @nullFlavor 0..1 cs Binding: CDANullFlavor (required)
.... xmlText 0..1 st Allows for mixed text content
... @representation 0..1 cs Fixed Value: TXT
... @mediaType 0..1 cs Fixed Value: text/plain

doco Documentation for this format

Terminology Bindings

Path Status Usage ValueSet Version Source
ST.nullFlavor Base required CDANullFlavor 📦1.0.1 This IG

Constraints

Id Grade Path(s) Description Expression
text-null error ST xmlText and nullFlavor are mutually exclusive (one must be present) (xmlText | nullFlavor).count() = 1

This structure is derived from ANY

 

Other representations of profile: CSV, Excel