Mapping procedures for the Claim resource within the Financial module

Looking for some guidance on mapping payer claim data to the FHIR Claim resource within the Financial module, and in particular, how to map the various procedure codes. Given that there are potentially multiple ICD procedure codes and/or one CPT procedure code for a given claim line, is there a best practice for which elements/resources within the Financial Claim data model are chosen?

In the medial claim example on the FHIR website, the ICD procedure codes were mapped under Claim.procedure (Claim.procedure.procedureCodeableConcept.coding.code) while the CPT procedure code was mapped under Claim.item (Claim.item.service.coding.code).

The follow-up to this is where the procedure modifier codes should be mapped.

Claim.procedure is intended to list any relevant interventions, which may be ICD procedure codes with modifiers or other procedure (intervention) code systems depending upon jurisdiction. Note that usually procedures aren’t specified, only billing codes are always specified. The billing code (CPT, HCPCS, CCI, ACHI, USCLS, etc. depending upon jurisdiction) is always specified. See the CMS1500 and UB04 mapping spreadsheets for further guidance.