Da Vinci PAS (Prior Authorization Support): HL7 FHIR Claim/$submit, CRD/DTR Triad, and X12 278 Mapping

Da Vinci PAS (Prior Authorization Support) is the HL7 Fast Healthcare Interoperability Resources (FHIR) Implementation Guide developed by the HL7 Da Vinci Project that enables electronic health records (EHRs) to assemble, submit, and receive real-time prior authorization determinations directly from health plans using FHIR R4 APIs. Operating as the third stage of the Da Vinci Burden Reduction triad alongside Coverage Requirements Discovery (CRD) and Documentation Templates and Rules (DTR), Da Vinci PAS is the federally recommended technical standard for the Prior Authorization API mandated under the CMS-0057-F Interoperability and Prior Authorization Final Rule.

What Is Da Vinci PAS and How Does the CRD–DTR–PAS Triad Work?

In the HL7 Da Vinci architecture, automated prior authorization is divided into three sequential, modular Implementation Guides so that clinicians discover payer rules, complete clinical questionnaires, and submit the authorization request without leaving the EHR workflow:

Burden Reduction Stage	HL7 Da Vinci Implementation Guide	Core Technical Mechanism	Workflow Input & Output
1. Discover Coverage Rules	Da Vinci CRD (Coverage Requirements Discovery)	HL7 CDS Hooks (order-select, order-sign, appointment-book, encounter-start)	Sends order/patient context to the payer; returns a coverage-information system action stating whether prior authorization (PA) or clinical documentation is required
2. Gather Clinical Documentation	Da Vinci DTR (Documentation Templates and Rules)	SMART on FHIR app or native EHR engine executing FHIR Questionnaire + Clinical Quality Language (CQL)	Fetches payer CQL rules and questionnaires, pre-populates discrete answers from the EHR chart, and outputs a signed QuestionnaireResponse
3. Submit & Adjudicate Request	Da Vinci PAS (Prior Authorization Support)	FHIR RESTful operations Claim/$submit and Claim/$inquire with PASClaim and PASClaimResponse profiles	POSTs the PAS Request Bundle (order + clinical attachments + DTR QuestionnaireResponse) and returns a synchronous PASClaimResponse determination

How Do Da Vinci PAS Claim/$submit and Claim/$inquire Operations Work?

Defined in the HL7 FHIR Da Vinci Prior Authorization Support (PAS) STU 2.0+ Implementation Guide, PAS standardizes both the clinical payload and the administrative transaction semantics:

• The PAS Request Bundle (POST [base]/Claim/$submit): The provider’s EHR constructs a FHIR Bundle (with Bundle.type = 'collection') whose first entry is a PASClaim (or PASClaimUpdate) resource representing the requested item, service, or inpatient admission. Subsequent entries in the same Bundle include the referencing Patient, Subscriber, Coverage, ordering/rendering Practitioner or Organization, and supporting clinical documentation (such as the DTR QuestionnaireResponse, DocumentReference PDFs, or discrete lab Observation resources).
• Synchronous Real-Time Response (PASClaimResponse): Within seconds (up to a maximum 15-second timeout in the IG), the payer endpoint returns a PAS Response Bundle containing a PASClaimResponse resource. Each requested line item carries a standardized X12/PAS review action code in the reviewAction extension:
  • A1 (Certified in Total): Approved in full; includes the prior authorization tracking number (preAuthRef) and effective date period (preAuthPeriod).
  • A2 (Certified — Partial): Approved with modified quantity, units, or duration.
  • A3 (Not Certified): Denied; under CMS-0057-F, the payer must include specific denial reason codes and clinical rationale so the provider can correct or appeal.
  • A4 (Pended): Requires manual medical director review or additional documentation.
  • A6 (Modified): Service modified by reviewer.
• Handling Pended Requests (Subscriptions and Claim/$inquire): When a request initially returns A4 (Pended), Da Vinci PAS supports two mechanisms to deliver the final determination once medical review completes: (1) event-driven push notification using HL7 FHIR Subscriptions (notifying the EHR webhook when the PASClaimResponse updates), or (2) provider-initiated status inquiry via POST [base]/Claim/$inquire using a PASClaimInquiry bundle.

How Is Da Vinci PAS Used in Healthcare and Regulated Under HIPAA X12 278 & CMS-0057-F?

1. Bridging HIPAA ASC X12N 278 (005010X217) and Pure FHIR: Because the HIPAA Administrative Simplification regulations (45 CFR § 162.1302) originally mandated the ASC X12N 278 transaction for health care services review, the Da Vinci PAS IG was meticulously mapped element-by-element to X12 278 loops and segments so clearinghouses or payer gateways can translate `PASClaim` JSON into X12 278 EDI and back. Furthermore, in February 2024, CMS announced HIPAA enforcement discretion confirming that covered entities that implement an all-FHIR Prior Authorization API using Da Vinci PAS without translating to X12 278 will not face HIPAA administrative simplification penalties.
2. CMS-0057-F Compliance Timelines: Under CMS-0057-F (89 FR 8758), Medicare Advantage organizations, state Medicaid and CHIP FFS programs, Medicaid managed care plans, and Qualified Health Plan (QHP) issuers on the Federally-facilitated Exchanges must deploy a FHIR Prior Authorization API by January 1, 2027, while enforcing decision turnarounds of 72 hours for expedited requests and 7 calendar days for standard requests starting in 2026.
3. Specialty Oncology and Clinical Research Trials: In oncology and complex specialty care—where treatment protocols combine standard-of-care imaging or infusion drugs (requiring payer prior authorization via Da Vinci PAS) with investigational trial arms—automated CRD/DTR/PAS workflows prevent treatment initiation delays that would otherwise violate protocol screening windows.

Frequently Asked Questions

What is da vinci pas?

Da Vinci PAS (Prior Authorization Support) is an HL7 FHIR Implementation Guide developed by the Da Vinci Project that defines how EHRs submit prior authorization requests and status inquiries to payers using FHIR R4 Claim/$submit and Claim/$inquire operations and receive structured PASClaimResponse approvals, denials, or pended statuses.

How is da vinci pas used in clinical research and healthcare?

In healthcare delivery and clinical trials, Da Vinci PAS works alongside Coverage Requirements Discovery (CRD) and Documentation Templates and Rules (DTR) to automate point-of-order prior authorization inside the EHR, satisfy the CMS-0057-F Prior Authorization API mandate, and eliminate manual portal/fax delays before initiating procedures, diagnostic imaging, or standard-of-care oncology regimens.