FHIM Model

The Federated Health Information Model (FHIM) uses Unified Modeling Language (UML) to describe a vast amount of health-related information required by over 20 US federal agencies (such as VA, DoD, HHS, and others) to achieve interoperability with internal and external systems.  The FHIM is a Logical Information Model, suitable to guide the Enterprise Architecture of healthcare organizations.  As shown below, it has 42 domains (such as lab, cardiology, procedures).  Each domain includes "classes."  There are over 1,000 in all.  Each class includes "elements."  There are over 6,000 unique elements in the FHIM.  As you examine the FHIM, note that the diagrams also include grey "enumeration" boxes in the diagrams.  These grey boxes list the terminologies "bound" to a given domain, class, or element.  Otherwise, the terminology bindings are hidden from the user.

The FHIM is aligned with existing and emerging healthcare IT standards, such as those issued by HL7 and IHE, and those endorsed or profiled by the US Office of the National Coordinator for Health Information Technology (ONC) for incorporation into various regulations.

However, the relevance of the FHIM is NOT limited to the US Federal Government or even to US healthcare.  The FHIM is a superset of all the standards (primarily from HL7, NCPDP, and ASC X12) that the US Federal Government (or any other US-based healthcare organization) would implement.  Outside the use of ASC X12 concepts in the Enrollment, Eligibility, and Coordination of Benefits domain, and the use of SNOMED and RxNorm codes in FHIM Value Sets, the FHIM is not even US-centric.  The FHIM can and has been used outside of the United States – especially for clinical domains.

One of the primary goals of the FHIM is to enable meaningful information exchange within, between, and among stakeholders in a healthcare community.  Therefore, the FHIM provides a semantic information basis for information exchange, traceability, and alignment into industry information models and standards.  FHIM classes and attributes are modeled so they can be easily transformed into intermediate models from which industry-standard artifacts can be generated.  The FHIM currently supports transforms to HL7 FHIR, HL7 CDA, and NIEM, but other standards are envisioned, including HL7 version 2, NCPDP, ASC X12, Oracle, Java, etc.  The FHIM has also adopted a modeling style that aligns with the HL7 Clinical Quality Framework such that there is a clear boundary between clinical concepts (which would bind into clinical terminologies) and the context in which the concepts are used. This pattern enables generation of clinical artifacts suitable for automated workflow, automated clinical decision support, reasoning, and secondary uses such as medical research.

Please Note: the FHIM is a single, very large, integrated healthcare information model.  Each UML-based domain diagram provides a view into part of the model.  Each diagram shows only a portion of the model; otherwise, it would become too unwieldy to navigate.  When a class in a diagram comes from a different domain, it will contain "(from)" beneath the class name, which defines the domain containing that class.  Whenever you see a class on a diagram that contains "(from)", please view that domain for more information on what other relationships that class may have.




  • 1 FHIM UML modeling complete
  • 2 Unchanged from the VHIM
  • 3 Previously modeled but in need of an update
  • 4 FHIM UML modeling in process


NOTICE: The use of any code system referenced in the FHIM model is governed by the license requirements of the specific code system noted. Please refer to the code system authority for use restrictions.