Talk:HL7 proposed guidance on use of displayName(V3 CD) and Text (V2.x CNE,CWE)

Outstanding issue(s):

1. Interface terms that are not supported by code systems currently do not have a place in the CD data type. The following options need to be considered:
   1. Original text may be used if the CD.code value is not already derived from prior supplied original text value (dangerous).
   2. Translation may be used if the interface term is supported by another code system.
   3. There is no capability in the current CD, CNE or CWE data types to specify the desired interface term (term to display to the user). Proposals to address this should be submitted.
      1. e.g. Add new data type component "Preferred Display Text". This field represents the sender's desired representation of the concept to the receiver. The preferred text may be an approved description from the code system or alternative text that does not alter the meaning of the concetp as defined by the code system.
2. Need to add guidance for use of original text (who is the originator?)
3. How do extension terminologies work in this environment? Give examples for each code system.
   1. LOINC - LOINC currently only supports three types of display text; fully specified name, short common name and long common name. As long as a LOINC extension conforms to the current rules for extending the terminology, any of these three representations would be valid to include as the description in any of the data types.
   2. SNOMED CT - Given that there is no currently approved way to specify a description ID in a message, there is no difference in the use of an extension description or a core concept description.
4. Post-coordination in v2.x? Use of displayname for postcoordinated expressions? (pending outcome of post-coordination task for OO)