CRD, DTR, and PAS Explained in Layman’s Terms 

Prior authorization is one of the most complicated workflows in healthcare. Endless phone calls, payer portals, faxed medical records, and manual reviews create friction for providers, health plans, and patients alike. That’s one reason new regulations from the Centers for Medicare and Medicaid Services (CMS) are pushing the industry toward digital prior authorization. 

One key rule, CMS-0057-F, focuses on modernizing prior authorization through standardized APIs and interoperable workflows. Three technical frameworks now work together to automate the process: Coverage Requirements Discovery (CRD), Documentation Templates and Rules (DTR), and Prior Authorization Support (PAS). 

These frameworks were developed through the HL7 Da Vinci Project and rely on FHIR interoperability standards to exchange information between electronic health records (EHRs), payer systems, and prior authorization platforms. Modern solutions increasingly act as orchestration layers between these systems, helping health plans digitize policies, automate workflows, and route requests to the appropriate clinical and utilization management tools. 

The Three-Step Workflow Behind Digital Prior Authorization 

In a modern ecosystem, CRD, DTR, and PAS work together to guide clinicians through prior authorization inside their existing workflows, whether through an EHR, payer portal, or SMART on FHIR web application. 

Each step solves a different problem: 

  • CRD: Determines what the health plan requires (“is prior auth required?”) 
  • DTR: Collects the right clinical information 
  • PAS: Submits the request electronically and communicates with utilization management systems 

Together, they create a connected workflow that replaces fragmented manual processes with structured, standards-based automation. 

Many organizations are also moving toward policy-driven orchestration platforms that connect CRD, DTR, PAS, policy management, and auto-authorization services into a single ecosystem. These platforms can evaluate procedure codes against payer policy rules, dynamically generate questionnaires, collect attachments, and package submissions into interoperable FHIR transactions. 

CRD: Finding Out if Prior Authorization Is Required 

Coverage Requirements Discovery begins when a clinician orders imaging, a procedure, medication, or another service. The EHR or provider portal sends information about the patient, diagnosis, and requested service to the payer or interoperability platform using FHIR APIs. 

The responding system evaluates payer policy rules and returns guidance in real time, including: 

  • Whether prior authorization is required 
  • Coverage restrictions 
  • Applicable medical policies 
  • Required documentation or questionnaires 
  • Routing instructions to internal or external clinical content providers 

Modern CRD platforms often support both internally managed policies and third-party policy sources such as MCG or InterQual. Depending on the configuration, the CRD workflow may dynamically direct the clinician to either a locally managed questionnaire or an external workflow managed by a delegated clinical criteria vendor. 

This helps providers understand requirements before the order is finalized, reducing surprises, resubmissions, and downstream denials. 

DTR: Gathering the Documentation the Plan Needs 

If CRD determines that authorization is required, the next step is Documentation Templates and Rules. DTR frameworks guide clinicians or support staff through collecting the necessary clinical documentation in a structured format. 

Many modern solutions maintain digitized copies of payer medical policies and convert those policies into dynamic DTR questionnaires tied to procedure codes and authorization rules. These questionnaires can include: 

  • Policy-specific clinical questions 
  • Generic question sets 
  • Conditional logic and branching 
  • Required documentation requests 
  • Attachments such as patient records or imaging reports 

In advanced workflows, questionnaires may be served from locally maintained policy libraries or dynamically redirected to external systems maintained by organizations such as MCG. This allows payers to preserve a single workflow while leveraging multiple clinical content sources. 

Because DTR questionnaires are structured and interoperable, EHRs and portals can automatically populate portions of the request using available patient data. Clinicians then add any missing information before submission. This reduces manual chart review, duplicate data entry, and incomplete submissions. 

PAS: Submitting the Prior Authorization Request 

The final step is Prior Authorization Support. Once the required information is collected, PAS packages the clinical documentation into a formal authorization request and submits it electronically. 

Modern PAS platforms do more than simply transmit data. Many also evaluate requests using configurable authorization rules before submission to determine whether requests can be automatically approved, pended for review, or escalated for additional evaluation. 

PAS workflows often act as the bridge between modern FHIR-based workflows and existing utilization management infrastructure. Once packaged into a FHIR-compliant transaction, the request is transmitted to the payer’s utilization management system of record. 

The payer may then: 

  • Acknowledge receipt 
  • Approve the request 
  • Deny the request 
  • Request additional information 
  • Route the request for clinical review 

Some advanced platforms also use AI-assisted clinical review tools to evaluate requests that cannot be automatically approved. These tools can analyze medical policies, DTR responses, procedure codes, and uploaded medical records to support clinician decision making during manual review. 

How This Process Improves the Provider Experience 

When implemented effectively, CRD, DTR, and PAS create a far more connected prior authorization experience. 

Key benefits include: 

  • Fewer delays and resubmissions 
  • Reduced manual administrative work 
  • Better alignment between policies and questionnaires 
  • More complete clinical submissions 
  • Improved visibility into authorization requirements 
  • Faster turnaround times 
  • Greater consistency in medical necessity review 
  • Better interoperability between payer and provider systems 

These improvements benefit patients as well by reducing last-minute denials, treatment delays, and unexpected financial impacts. 

A Simple Example 

Let’s say a provider orders an MRI. Here’s how a modern interoperable workflow may operate: 

  • A CRD request is initiated from the EHR or payer portal 
  • The platform determines that prior authorization is required 
  • The clinician is directed to the appropriate DTR questionnaire 
  • Relevant patient history is automatically populated where available 
  • The clinician adds any missing clinical information and attachments 
  • PAS packages the request into a FHIR-compliant authorization submission 
  • Authorization rules evaluate whether the request can be automatically approved 
  • The completed request is transmitted to the payer’s utilization management system 
  • The entire process occurs within an integrated digital workflow rather than through disconnected phone calls, faxes, and manual data entry. 

The Future of Prior Authorization 

Digital prior authorization is evolving beyond simple electronic submission. Health plans are increasingly adopting interoperable platforms that combine policy management, CRD, DTR, PAS, automation, and AI-assisted review into unified ecosystems. 

The goal is not simply compliance with CMS-0057. The larger objective is reducing friction across the healthcare system while creating faster, more accurate, and more transparent authorization workflows for providers, payers, and patients alike. 

At Itiliti Health, we support next-generation prior authorization management. Want to learn more? Contact Itiliti Health and discover a better way.