SNOMED Change Requests: Issues and Discussion

Issue 1: Determination of Needed Concepts

How will the proposed policy support determining what concept changes or additions are required to SNOMED.

Issue 2: Evaluation of Existing SNOMED Content

How can the HL7 process ensure that sufficient due diligence and analysis has been performed on the existing SNOMED content.

Is the requested content already represented? If so, is it just represented in a context different than what was expected?

Issue 3: International Versus Realm Specific Usage

How can the HL7 policy make a clear delineation between International vs. Realm specific change requests? Can (or should) the HL7 process be used to support Realm specific requests that would be funneled through a National Release Center (NRC)? Should the HL7 process be used to vet the change requests and direct Realm specific changes to the appropriate NRC? For an international submission, how would the responsible contact be assigned/managed?

Issue 4: Pre-coordinated vs. Complex Expression

SNOMED policy with regards to acceptance of new pre-coordinated terms is currently being reviewed. In some cases pre-coordination of complex concepts will not be allowed. HL7 needs to determine if and when post-coordinated expressions are acceptable.

Alternatively, HL7 needs to determine if concept domains need to be represented in a consistent manner, i.e. all complex concepts must be represented as expressions or a mix of pre-coordinated and post-coordinated terms will be allowed within a domain range.

Issue 5: Fully Modeled vs. only Term + Definition Submission

Should the process require fully modeled changes, term plus definition, or both?

Full modeling requires a detailed understanding of the SNOMED Concept Model. Partial modeling of a term does not provide much more benefit to the IHTSDO modelers than a detailed definition or reference. If full modeling were required, tooling to support the concept model would be required in order to determine compliance.

Issue 6: Appropriateness of SNOMED

How does HL7 determine whether SNOMED is the appropriate terminology to use for a particular concept domain? Since there is considerable overlap of content among standards, what is the process to decide that SNOMED is the best one, especially if the proposed content is poorly represented in the terminology hierarchy currently?

Issue 7: SNOMED Licensing

HL7 doesn't provide any type of SNOMED CT sub-licensing. Implementers of HL7 standards based on SNOMED must obtain their own license.