Terminology Syndication Feed Implementation Guide, published by Australian e-Health Research Centre. This guide is not an authorized publication; it is the continuous build for version 0.1.0 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/FHIR/fhir-syndication-ig/ and changes regularly. See the Directory of published versions

NCTS ASF Extensions

NCTS ASF Extensions

Namespace URI: http://ns.electronichealth.net.au/ncts/syndication/asf/extensions/1.0.0 Conventional prefix: ncts

The NCTS Atom Syndication Format extension namespace carries the core terminology metadata that distinguishes a terminology syndication feed from a generic Atom feed.

Feed-level elements

<ncts:atomSyndicationFormatProfile>

URI declaring the ASF profile version the feed conforms to.

Cardinality	Type	Where
0..1	xs:anyURI	inside <feed>

Current value: http://ns.electronichealth.net.au/ncts/syndication/asf/profile/1.0.0.

MUST be present whenever any NCTS ASF extension element appears in the feed.

Entry-level elements

<ncts:contentItemIdentifier>

Canonical, version-independent identifier of the artefact.

Cardinality	Type
1..1	xs:anyURI

Stable across versions of the same logical artefact. For FHIR canonical resources, equals the resource's url. For SNOMED CT modules, the unversioned module URI.

<ncts:contentItemVersion>

Canonical, version-specific identifier of this exact release.

Cardinality	Type
1..1	xs:anyURI

MUST be unique per <entry> within a feed. For FHIR canonical resources, equals <url>|<version>. For SNOMED CT modules, the versioned module URI (http://snomed.info/sct/<moduleId>/version/<YYYYMMDD>).

<ncts:fhirVersion>

FHIR version the artefact targets.

Cardinality	Type
0..1	string, max length 5, format <major>.<minor> or <major>.<minor>.<patch>

MUST be present when at least one of the entry's <category> elements has a FHIR_* term in the NCTS ASF scheme.

<ncts:fhirProfile>

FHIR StructureDefinition canonical(s) the artefact claims conformance to.

Cardinality	Type
0..*	xs:anyURI

Repeats once per profile. Only meaningful for FHIR artefacts.

<ncts:bundleInterpretation>

For artefacts that are FHIR Bundles: a publisher hint describing how the publisher views the Bundle's contents.

Cardinality	Type	Permitted values
0..1	code	batch, collection

The value indicates why the Bundle is included in the feed — either as an independent batch of operations (batch) or as a curated collection of resources (collection). Codes correspond to the FHIR Bundle.type value set.

This is a hint, not a directive. A consumer that retrieves the Bundle remains free to process it however it sees fit, and is not obliged to use the publisher's interpretation. Absence means the publisher offers no hint and the consumer has full discretion; it is not a default value.

Link-level attributes

ncts:sha256Hash

Lowercase-hex SHA-256 of the artefact byte stream. 64 hex characters. Used as an attribute on <link>.

When both sct:md5Hash and ncts:sha256Hash are present on the same link, ncts:sha256Hash is authoritative.