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VSAC Support Center

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NLM releases VSAC FHIR R4

The NLM Value Set Authority Center (VSAC) is pleased to announce the migration of our Fast Healthcare Interoperability Resources (FHIR®) Terminology Service for VSAC value sets and code systems from FHIR v3.1.0 (R3) to FHIR v4.0.1 (R4).

FHIR, created by Health Level Seven International (HL7), is designed to enable information exchange to support the provision of healthcare in a wide variety of settings.

The FHIR Terminology Service for VSAC Resources is a RESTful API service for accessing the current VSAC value sets and supported code systems. This service requires a free Unified Medical Language System® Metathesaurus License due to intellectual property and usage restrictions on some of the codes included in value sets.

We currently support the following FHIR Terminology Module resources and corresponding operations:

These FHIR resources can access value sets published through VSAC as well as code systems hosted by VSAC.

With this migration from FHIR R3 to FHIR R4, we are also enabling login-free FHIR R4 API access to the following:

FHIR API implementers should use the new Base URIs:

In the near future we will deprecate support for the previous FHIR R3 Base URI:

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Last Reviewed: July 9, 2021