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FHIR Infrastructure Work GroupMaturity Level: N/ABallot Status: Informative

Health Level Seven (HL7) has been developing healthcare information exchange and related standards since 1987. In that time, the organization has produced a number of standards families - many used throughout the world to automate healthcare data sharing and improve patient care. FHIR has been written to be implementable without any knowledge of these other specifications. However, FHIR does leverage this prior experience, both in terms of applying best practices learned from experience and attempting to avoid some of the pitfalls of earlier work.

This appendix describes the relationship of FHIR to some of HL7's other standard families. It may be of interest to those coming to FHIR with previous experience with other HL7 standards as well as those who may need to support interoperability between FHIR solutions and implementations of other HL7 standards.

In this appendix:


  • In addition to the major standards families identified below, HL7 produces numerous implementation guides, some of which have earned as much prominence as a standard family themselves. The general guidance given below for each standard family should hold for all implementation guides based on that standard. For example, the guidance listed for CDA would apply to Consolidated CDA (CCDA) and other CDA Implementation Guides.
  • While this appendix focuses on the relationship between FHIR and other HL7 standards, relationships also exist to non-HL7 standards. Some resources provide direct implementation of functionality from other standards including DICOM (see the ImagingStudy resource) and IHE (e.g. the AuditEvent and DocumentReference resources).
  • Many FHIR resources draw requirements from or provide mappings to other standards. Some resources also provide additional guidance on how to use them with external specifications as part of their implementation notes. As well, a wiki page to capture additional guidance on the use of FHIR with other specifications can be found here
  • FHIR can satisfy the needs covered by all of the previous primary HL7 interoperability standards (HL7 v2 , HL7 v3 and CDA). In many cases, it also provides additional benefits in terms of ease of interoperability. Therefore, the possibility exists that FHIR could gradually replace some or all of these standards. However, it is unclear how rapidly (or even if) the market will make such a migration. It is likely that most of these standards will exist in parallel for quite some time. HL7 has committed to ongoing maintenance of existing standards for as long as the HL7 membership requires.