Very CommonContractual Obligation (CO)Medical Necessity
CO-50: Non-covered service (not deemed medically necessary)
The payer has determined that the service is not covered because it is not medically necessary based on the diagnosis, clinical information, or coverage policy. This is a medical necessity denial, meaning the payer does not believe the clinical evidence supports the service performed.
Common Causes
- Diagnosis code does not meet the payer's medical necessity criteria for the procedure
- Service is experimental or investigational per the payer's coverage policy
- Frequency limits exceeded (e.g., more imaging studies than allowed per time period)
- Conservative treatment requirements not met before proceeding to advanced services
- Missing clinical documentation to support medical necessity
How to Resolve CO-50
- 1Review the payer's LCD/NCD or medical policy for the specific procedure
- 2Obtain additional clinical documentation from the provider to support medical necessity
- 3Submit a peer-to-peer review request with the payer's medical director
- 4File a formal appeal with a letter of medical necessity and supporting clinical evidence
- 5If the denial is upheld, pursue external review through the state insurance department
How to Prevent CO-50 Denials
- Check coverage criteria before performing the service
- Ensure documentation clearly supports the medical necessity of each procedure
- Use diagnosis codes that align with payer LCD/NCD coverage requirements
- Obtain prior authorization for services flagged as requiring medical necessity review
Related Denial Codes
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