CARC233ReferenceCurrentVerified Aug 15, 2026CARC 233
AR Guide Workflow
Medical Necessity
The payer determined the service was not medically necessary or reasonable according to its policy. These denials are documentation-driven.
AR Guide explanation
What it means
Services or charges relate to treatment of a hospital-acquired condition or preventable medical error.
AR Guide knowledge
Common denial category
Medical Necessity — The payer determined the service was not medically necessary or reasonable according to its policy. These denials are documentation-driven.
AR Guide knowledge
Common causes
- Hospital-acquired condition present
- Preventable complication per CMS/payer rules
AR Guide knowledge
What AR should verify
- Review the documentation of the condition
- Confirm whether the condition was present on admission
AR Guide knowledge
Recommended action
- If the condition was present on admission and documented, appeal with that documentation
- If not documented at admission, the denial may stand
About this guidance: Note
AR Guide knowledge is general reference content written by our team — it is not payer-specific policy and never replaces the payer’s documentation or your contract. Always confirm specifics with the payer.