Some Medicare plans require authorization from Medicare prior to providing specific covered services. This authorization is about cost-savings and not whether or not the plan offers the care.
If a plan provides a benefit, it covers that benefit. Prior authorization requirements just require the plan to verify with Medicare before providing the service to ensure the care has been pre-approved by Medicare.
This is different than requiring a referral from a healthcare provider. However, some benefits may require both.
- Medicare Prior Authorization. MedicareAdvocacy.org.