X12 278 Prior Authorization

1. 278 request structure

   UM loop for health services review, patient event, service and provider loops, and request category codes.

2. 278 response

   HCR health care services review decision, reason codes and authorization numbers.

3. CMS prior authorization rule

   CMS-0057-F requirements for prior authorization APIs, decision timeframes and metrics.

4. Da Vinci PAS

   FHIR-based prior authorization with a 278 conversion at the payer boundary.

5. Da Vinci CRD and DTR

   Coverage requirements discovery and documentation templates before submitting prior auth.

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