ELGA is CDA and IHE: Austrian FHIR Core is a different stack
ELGA production is still CDA document exchange over IHE XDS. HL7 Austria Core R4 2.0.0 is the FHIR baseline. Austrian Patient Summary FHIR is not live ELGA. Social security number uses urn:oid:1.2.40.0.10.1.4.3.1.
Ala Ben Aicha
Direct answer
ELGA production is CDA documents over IHE XDS, not FHIR. HL7 Austria Core R4 2.0.0 is the FHIR baseline. Austrian Patient Summary FHIR is not live ELGA. SSNr system is urn:oid:1.2.40.0.10.1.4.3.1.
Do not rebadge ELGA as FHIR
ELGA (Elektronische Gesundheitsakte) is Austria’s national EHR exchange. The binding implementierungsleitfäden published under § 16 ELGA-VO 2015 are HL7 CDA documents registered with IHE XDS metadata. HL7 Austria’s own Core IG says ELGA is mainly based on CDA, and that the Core IG exists so FHIR resources can resemble that structure. That is a mapping story, not a production cutover.
No cited 2026 ELGA specification on write day redefines the national EHR as a FHIR REST store. FHIR work is real — Core profiles, an Austrian Patient Summary IG, CDA-to-FHIR maps, a parent-child-pass FHIR API in development — and it is not the ELGA document backbone.
| Layer | Owner / home | Canonical / package | What it is | What it is not |
|---|---|---|---|---|
| ELGA CDA + IHE XDS | ELGA GmbH; CDA implementierungsleitfäden; ELGA standards | General CDA IG v3 OID 1.2.40.0.34.7.1.9.3; XDS metadata IG v3.0.2 OID 1.2.40.0.34.7.6.9.3; plus document-class IGs (e-Medikation, discharge, imaging, …) |
Production ELGA: structured CDA documents, XDS registration, permission system | Not FHIR. A CDA e-Medikation document is not NLLMedicationRequest |
| HL7 AT Core R4 2.0.0 (STU2, 27 Jan 2025) | HL7 Austria TC FHIR; fhir.hl7.at Core R4 | Package hl7.at.fhir.core.r4#2.0.0; Patient canonical http://hl7.at/fhir/HL7ATCoreProfiles/4.0.1/StructureDefinition/at-core-patient |
Austrian FHIR baseline for Patient, Address, Organization, Practitioner; CDA header mappings | Not ELGA onboarding, not a document registry |
| Austrian Patient Summary (APS) 1.0.0 (STU1, generated 17 Feb 2026) | ELGA GmbH / HL7 Austria; APS R4 | Official URL https://fhir.hl7.at/elga/aps/r4/ImplementationGuide/hl7.at.fhir.elga.aps.r4; package hl7.at.fhir.elga.aps.r4#1.0.0 |
FHIR R4 Patient Summary aligned with IPS / MyHealth@EU requirements catalogue. Current published version at that URL | Not production ELGA, not a replacement for CDA Patient Summary |
| ELGA FHIR facades (in development) | ELGA; dev.elga.gv.at | e.g. eEKP FHIR-Anbindung v1.2.0 listed as in development | Named FHIR APIs in front of ELGA services | Not “ELGA is FHIR now” |
Primary sources: ELGA CDA publication list, HL7 AT Core R4 2.0.0. Swiss EPD is a document/IHE neighbour, not a clone — see Swiss EPD. European IHE patterns: IHE in European healthcare.
The identifier: social security number
Country-specific identifier on HL7 AT Core Patient is the Austrian social security number (SSNr), slice identifier:socialSecurityNumber:
urn:oid:1.2.40.0.10.1.4.3.1
Type code SS from v2-0203. Other slices exist (local identifiers, ELGA-related ids as the profile defines them). Do not publish a real SSNr. Keep the system URL and a dummy value in fixtures.
ELGA-ID in CDA headers is a document-identity concern mapped in the Core Patient CDA mappings. It is not a reason to skip SSNr on a FHIR Patient that claims AT Core.
What to implement first
- If the buyer is an ELGA GDA / document source: CDA document class named in the contract, XDS metadata, ELGA permission system. FHIR is optional façade work, not the submission format.
- If the buyer wants Austrian FHIR Patient for a new API: HL7 AT Core R4 2.0.0, SSNr system as above.
- If the buyer names Austrian Patient Summary / IPS: APS 1.0.0, and say out loud that ELGA production is still CDA.
- For EHDS category 1, do not assume ELGA CDA is EEHRxF. Overlay EU Core when the contract is European payloads.
What this is not
This article is not ELGA certification, not an IHE Connectathon report, not a GDA contract, and not legal advice. Implementing AT Core profiles does not connect you to ELGA. I do not perform ELGA onboarding. Nothing here is clinical advice.
Related reading
For ELGA document / FHIR hybrid architecture, use digital health interoperability or start a project.