Following up on the discussion today about identifiers to be passed from PAS to DTR when we’re using the LOINC code indicating that there should be a DTR launch-

We’ve heard payers need both questionnaires at the overall auth level and the individual service level. This is supported using the DTR LOINC code by:

• event level LOINC codes in 2000E HI, which map to ClaimResponse.communicationRequest[n]
• service level LOINC codes in 2000F HI, which map to ClaimResponse.communicationRequest[n] with extension-serviceLineNumber populated

In terms of related identifiers on the 278R response, the:

• event level tracking numbers in 2000E TRN, which map to ClaimResponse.identifier[n]
• service level trace numbers in 2000F TRN, which map to ClaimResponse.item[n].extension(itemTraceNumber)

Can both be generated by either the provider side (we would generate them on the request and then the payer would echo them back on the response) or the payer side (they generate them as part of the response).

You can tell which system generated the identifier by looking at TRN03, which gets mapped to identifier.system. Based on that, a provider system knows whether it generated the identifier or if it was payer-generated.

So if a payer wants to support responding with a DTR LOINC code with an associated tracking number that their DTR questionnaire package operation is able to understand, I think that should use a payer generated TRN.

Then on the provider side we would look at each ClaimResponse.communicationRequest, and each time we see the DTR LOINC code we would make available a CDex DTR launch using the relevant identifier (if it’s associated with a claim item and that item has a payer-generated itemTraceNumber then use that, otherwise use the payer-generated ClaimResponse.identifier).

Side note, I ran into some confusion in glass, the service level TRN mapping is clear about supporting multiple originating systems by saying “extension[n]”, but the event level TRN mapping is less obvious by saying “identifier[0]” when it should say “identifier[n]” - we probably want to clarify that.