Coverage Requirements Discovery (CRD)

Overview

The Aidbox Coverage Requirements Discovery (CRD) implementation enables real-time communication between EHR systems and payers to determine documentation and prior authorization requirements at the point of care. Built on the HL7 Da Vinci Coverage Requirements Discovery Implementation Guide , it helps providers understand payer requirements before ordering services.

When combined with Documentation Templates and Rules (DTR) and Prior Authorization Support (PAS), CRD ensures that providers are informed of coverage requirements early in the workflow, reducing claim denials and improving the authorization process.

CDS Hooks

The core of the CRD Implementation Guide is built on CDS Hooks — an HL7 standard that enables clinical decision support to be invoked from within a clinician's workflow. All hooks in the CMS-0057-F Aidbox module follow the same processing workflow:

1. 1.

   Receive Hook Request — The EHR system sends a CDS Hooks request (e.g., order-sign, order-select) containing context data (patientId, encounterId, draftOrders etc.) and prefetch resources.

2. 2.

   Validate Request Structure — The request is validated against the CDS Hooks schema to ensure all required fields are present and correctly formatted.

3. 3.

   Validate FHIR Resources — All FHIR resources from draftOrders and prefetch are validated together using Aidbox validation. This includes resolving all references within each resource.

4. 4.

   Fetch Missing Resources — If validation fails due to missing referenced resources, the module automatically fetches them from the fhirServer URL provided in the hook request using the fhirAuthorization token. This resolution continues recursively until all references are resolved.

5. 5.

   Persist Resources — All validated resources are persisted to Aidbox using a transaction bundle for audit and future reference.

6. 6.

   Enrich and Proxy — The request is enriched with resolved prefetch data and proxied to the configured decision-making service, which analyzes the clinical data and returns CDS Cards with coverage requirements, documentation needs, or prior authorization information.

Decision Making Service

The CMS-0057-F Aidbox module (healthsamurai/cms-0057:edge) proxies validated CDS Hooks requests to an external decision-making service. To configure the decision service URL, set the following environment variable:

CDS_DECISION_SERVICE_URL=https://your-decision-service.example.com

For a complete setup example, see Run Aidbox + CMS App locally.

It is the responsibility of the decision-making service to analyze the clinical data and build a valid CDS Hooks response containing appropriate Cards with coverage requirements, prior authorization information, or links to SMART apps for additional documentation gathering.