Special Vocabulary Considerations for Harmonization Processes
Bound Value Set Changes
Many existing Value Sets have defined Context Bindings in the current vocabulary. Occasionally, changes to one or more of these Value Sets are brought as proposals to a Harmonization Meeting. When proposed changes are submitted to a Value Set that has one or more Context Bindings currently existing, a number of specific questions must be considered based upon the type of proposed change(s):
- Is the Value Set being deprecated?
When a bound Value Set is deprecated, the binding(s) must be evaluated. Either they also must be deprecated, or they should be changed to identify a different Value Set that is not deprecated. In either case, text documentation describing the binding change and the reason(s) for it must be submitted.
- Is the definition change to the Value Set resulting in a change to the semantic coverage?
When the coverage space of a Value Set changes, it may no longer be appropriate for an existing use. The binding(s) that exist must be examined, and if the desire is to keep the bindings to the old Value Set, then the bindings must include the Value Set Version in the Value Set Assertion so that the old binding(s) continue to point to the original unchanged Value Set. If the new Value Set is to be used for the existing bindings, some effort should be undertaken to research where they are used, and by whom, and notify them of the proposed change. This must be documented in the proposal for Harmonization.
Bound Value Set Removal
A proposal may be brought to Harmonization to remove an existing Value Set that has one or more existing Context Bindings. In this case, the following must be considered:
- Is the Value Set being replaced?
When a Value Set is replaced, and existing bindings must be examined, and a determination be made if the replacement Value Set will continue to perform the same business function. If so, then the binding must be replaced as well, and an effort must be undertaken to notify the users of the model(s) that employ the binding of the change; this must be documented in the proposal. If it cannot be determined if the binding should be replaced, then a judgement of either removal of the binding, or change of binding Realm, perhaps to Example, should be suggested. Replacement of a Value Set generally results in deprecation or retirement of the original Value Set; processes to deal with the bindings in these circumstances should be followed.
- Is the Value Set being retired?
When a Value Set having an existing binding is retired, the binding must be changed. The options for change are:
- retire the binding (delete it) - This must be done with a statement of the effect on any models using the binding;
- replace the binding (point to a different Value Set) - This must be undertaken as part of the proposal, and contact with those that are using the binding must be documented;
- change the binding type - a Representative binding may be weakened by changing it to an Example binding; a Universal Binding can be weakened to a Representation or an Example binding. Bindings for a specific national Realm should not be modified as part of Harmonization, but should be undertaken by the Affiliate managing that Realm.
All changes to bindings must be documented in the Harmonization proposals, with their resolution and recommendations, the same as changes to other vocabulary elements. Failure to deal with existing bindings in a proposal to change or remove Value Sets are grounds for rejection during Technical Review of proposals.
This is a proposed policy, will be discussed for approval in March 2013
--TedKlein 16:07, 6 March 2013 (UTC)