Currently designation.use allows to specify that the designation is a synonym or a fully specified name. It is proposed that "Consumer-friendly term" is to be added to the value set.

By SNOMED standards, there are three distinct aspects that should be managed by designation.use:

• the description type (Synonym or Fully specified name (or Definition), <900000000000446008 |Description type (core metadata concept)|)
• the language reference set (e.g. 900000000000508004 | Great Britain English language reference set (foundation metadata concept) |, 281000210109 | NZ patient-friendly language reference set (foundation metadata concept) |, 500191000057100 | Laboratory medicine context language type reference set (foundation metadata concept) |. <900000000000506000 | Language type reference set (foundation metadata concept) |)
• the acceptability of the description in that language reference set (<900000000000511003 | Acceptability (foundation metadata concept) |)

Specification of these aspects would be required for both querying (term filtering) and for results ($lookup and $expand). $expand has distinct IN parameters whereas $lookup relies on properties. The language for X.display is specified by displayLanguage parameter for $lookup and $expand.

Proposal to create an extension to designation to allow unambiguous specification of the three aspects above.

Behavior when parameters are not specified (defaults) and/or when there are no descriptions meeting criteria (fall back) should be specified.