What is prior authorization in Medicare?

• A. It is a requirement by some CMS programs or private plans to obtain approval before the service is provided.
• B. It is a post-service review to determine payment.
• C. It is a feature of traditional Part A/B that always requires proof of patient consent.
• D. It is a process to determine the provider's credentialing.

Answer: (A)

Prior authorization is a pre-approval process required by some CMS programs or private plans before a service, procedure, or product is provided or billed. It’s a payer review to confirm medical necessity and coverage before care is delivered, so the provider can know in advance whether the service will be paid for. In Medicare, many standard Part A/B services don’t require prior authorization, but certain programs and private plans (including some Medicare Advantage plans) do require it for specific items like certain imaging, durable medical equipment, or particular drugs. If prior authorization isn’t obtained when needed, the service may not be covered or payment may be denied.

The other possibilities describe different concepts: a post-service review happens after care to determine payment, patient consent is about agreeing to treatment rather than approvals for coverage, and credentialing is about verifying the provider’s qualifications, not authorizing services.