Release 4
FHIR Management Group Maturity Level: N/AStandards Status: Informative
HL7 is an ANSI Accredited Standards Development Organization. As such, ANSI reviews HL7 processes both in general, and also specifically with regard to each standard. ANSI has certified that portions of this release of FHIR (Release 4) met its requirements for development of a formal standard.

Given that many areas of the FHIR specification are still undergoing Trial Use by the HL7 Community, and hence are not ready for balloting as a formal ANSI standard, and in order to manage the processes around the ballot process, four different portions of this specification were balloted as ANSI Normative Specifications:

Infrastructure The core framework on which FHIR solutions depend (Abstract base types, data types, formats, the RESTful API, and content and typing rules)
Conformance The terminology infrastructure and the base resources that define FHIR implementations and that represent how the specification, and conformance to it, is defined
Patient The Patient resource and related content
Observation The Observation resource and related content

For the purposes of American National Standards, each of these is an independent standard, and the other parts of the specification do not contain requirements necessary for conformance to the formal standard.

Given that the Normative parts of the standard are still a subset of what implementers need to use, implementers are generally focusing on conforming to FHIR R4 as a whole rather than the formal standards. Future versions of this specification will extend the coverage of format standards.