201709 Terminology Services Track

Return to Sept 2017 Proposals

Terminology Services

Submitting WG/Project/Implementer Group

FHIR Management Group (FMG)

Justification

The FHIR specification includes support for the provision of a terminology service - that is, a service that lets healthcare applications make use of codes and value sets without having to become experts in the fine details of the value set resource, and the underlying code systems. The management and proper use of terminology is fundamental to effective, interoperable data exchange, so this is an important capability to provide and test in the Connectathons.

David Hay's blog post on Terminology Services

Proposed Track Lead

Coordinator: Rob Hausam (There is a dedicated Zulip topic on the implementers stream for Terminology Services - https://chat.fhir.org/#narrow/stream/implementers/subject/Connectathon.20Terminology.20Services.20Track

Expected participants

• Health Intersections - server
• AEGIS - Touchstone tool and test scripts
• Apelon - Terminology Server (uid/pwd dtsadminuser/dtsadmin): http://fhir.ext.apelon.com/dtsserverws/fhir
• Lantana - FHIR services on Trifolia
• CSIRO - server
• NLM - FHIR services on VSAC
• IMO - FHIR services on IMO ProblemIT/ProcedureIT
• Patients First NZ - Server
• Health Language FHIR terminology services (new)
• Hausam Consulting test server
• Additional servers and clients

Roles

FHIR Terminology Server

For service providers, implement the following operations from http://hl7.org/fhir/terminology-service.html:

• $expand - Value Set Expansion
• $validate-code - Value Set Validation
• $lookup - Concept Lookup
• $subsumes - Subsumption Testing
• $translate - Concept Translation
• $closure - Maintaining a Closure Table

Support additional capabilities:

• Expansion Profile (experimental) - Expansion Profile FHIR Resource Proposal
• SNOMED CT and LOINC implicit value sets - [1] [2]
• Support ConceptMap, ValueSet resources and operations ($expand, $validate-code, $lookup) referencing code systems using the new CodeSystem resource (instead of ValueSet.codeSystem) - NEW

Service providers are not required to implement all of this functionality - it's a lot to do. For new implementers, start at the top and work down (generally).

FHIR Terminology Client Consumer

Implement any one or more of:

• Do a value set expansion of one of the value sets in the spec
• Validate a code using the spec against a FHIR value set, a v2 value set, or LOINC or snomed CT
• Look up a display for a code (most appropriate for v2/FHIR conversion)
• Translate a code from one value set to another, based on the existing value set and ConceptMap resources, and/or other additional knowledge available to the server
• Maintain a client-side closure table based on server-side terminological logic
• Experiment with the capabilities of the expansion profile (see description above of the expected capabilities and scenarios)
• References to SNOMED CT and LOINC implicit value sets
• Create (POST, PUT) ValueSet resources referencing in-line and/or external code systems
• Create and perform operations ($expand, $validate-code, $lookup) on ValueSet resources referencing code systems using the new CodeSystem resource (instead of ValueSet.codeSystem) - NEW

At least one server supports all of these operations and capabilities (http://fhir3.healthintersections.com.au). Other servers, including the Apelon server (http://fhir.ext.apelon.com/dtsserverws/fhir) and the others listed above will support several of these operations and capabilities. For a list of functions supported by the Apelon Server, see the demo web app (http://fhir.ext.apelon.com/DtsOnFhirDemo, uid/pwd dtsadminuser/dtsadmin).

TestScripts

The supporting TestScripts and corresponding fixtures have been committed to the FHIR SVN repository at: http://gforge.hl7.org/gf/project/fhir/scmsvn/?action=browse&path=%2Ftrunk%2Fconnectathons%2FMadridMay2017%2FConnectathon15%2FTerminology%2F [Will be updated for San Diego]