Most denials can be traced to preventable administrative or clinical documentation issues:

Contractors may determine a service was not "reasonable and necessary" for the patient's condition.

These include duplicate claim submissions, services performed by unqualified employees, or missing prior authorizations for certain equipment. The Appeals Process

If a claim is denied, you have a legal right to appeal the decision. For Original Medicare (Part A and B), there are five distinct levels of appeal: Medicare Program Integrity Manual, Chapter 6 - CMS