Why must Medicare claims document medical necessity?

• A. Documentation is optional for Medicare claims.
• B. Medical necessity is determined by patient preference alone.
• C. Medicare pays for medically necessary services; documentation supports the claim, and lack of documentation can lead to denials and enforcement actions.
• D. Documentation is required only for inpatient services.

Answer: (C)

Medicare pays for services that are medically necessary for the patient’s diagnosis or condition. To show that a service is reasonable, appropriate, and needed, the provider must document the clinical rationale, the patient’s condition and history, the diagnosis, the treatment plan, and the expected outcomes. This documentation becomes the evidence that the claim meets Medicare’s coverage criteria. Without it, a claim can be denied for lack of justification, and providers can face enforcement actions for noncompliance or improper billing. It isn’t based on patient preference, it isn’t optional, and it applies to more than inpatient services.