CodeSystem FHIR Resource Proposal

CodeSystem

Owning committee name

Vocabulary

Contributing or Reviewing Work Groups

• FHIR-Infrastructure

FHIR Resource Development Project Insight ID

Pending

Scope of coverage

The code system resource has the contents of ValueSet.codeSystem, which will be removed once the resource is adopted. The main change, therefore, is moving code system from being inlined in value set to being it's own first class resource. In addition, the scope of the code system representation expands:

• define the kind of filters that are supported by the code system (to allow smarter value set editing)
• define the kind of properties that the code system defines, and provide properties for the concepts

As for implementation scope: this is a universal infrastructure piece in a well understood domain (consistent with the v3 core principles, and the basic CTS 2 definitions)

Note that the scope does not include code system maintenance, only publishing the details of a code system (with or without the actual content)

RIM scope

out of scope for the RIM

Resource appropriateness

Codesystem:

• Represents a well understood, "important" concept in the business of healthcare
• Represents a concept expected to be tracked with distinct, reliable, unique ids
• it is Reasonable for the resource to be independently created, queried and maintained
• is already widely the subject of exchange and part of the value set resource
• is expected to contain an appropriate number of "core" (non-extension) data elements
• has the characteristics of high cohesion & low coupling, and is level 0 (infrastructure)

Expected implementations

All the terminology services, and the build tool, will all have to support the code system resource

Content sources

• ValueSet
• CTS 2
• Core principles
• VSD
• implementer feedback about ValueSet.codeSystem

Resource Relationships

Resources that will reference CodeSystem:

• ValueSet will reference this resource by canonical URL
• the Coding data type references this resource implicitly by canonical URL
• implementationGuide will reference this resource explicitly for publishing purposes

The creation of the CodeSystem resource will change the use of NamingSystem resource, since all of it's functionality related to code systems should now be moved to CodeSystem. This resource name should be changed to 'IdentifierSystem' and it's definition tightened accordingly.

Timelines

Target to trail the resource in the may 2016 connectathon, and to ballot it for DSTU3

gForge Users

• Grahame Grieve
• Rob Hausam