OA-9: Diagnosis Inconsistent with Patient Age

What Does OA-9 Mean?

With OA (Other Adjustments), CARC 9 typically appears in a coordination of benefits (COB) context. Age-diagnosis inconsistency caught during secondary payer processing. The financial responsibility depends on the specific arrangement between payers — review the primary payer's EOB and the COB terms to determine the correct course of action.

CARC 9 appears on a remittance when the payer identifies an issue related to diagnosis inconsistent with patient age. This is a technical billing or coding problem that must be corrected before the claim can be processed for payment. The denial indicates the claim data did not meet the payer's adjudication requirements.

Common scenarios that trigger this adjustment include: patient's DOB is wrong in the system, causing age to be calculated incorrectly for diagnosis validation; Diagnosis code has age restrictions that do not match the patient's actual age (e.g., pediatric condition coded for adult); Coder selected an ICD-10 code with age specificity that does not match the patient. The group code paired with CARC 9 determines who bears the financial responsibility — CO places it on the provider as a contractual obligation, OA indicates a coordination of benefits or other payer adjustment, PR shifts it to the patient.

Common Causes

How to Resolve

1. Review the coordination of benefits Examine the OA-9 adjustment to understand how it fits within the primary/secondary payer relationship or other multi-payer context.
2. Verify primary payer adjudication Review the primary payer's EOB to understand the basis for the secondary payer's OA adjustment.
3. Determine the responsible party Based on the COB review, identify whether the adjustment should be absorbed, billed to another payer, or if additional documentation is needed.
4. Appeal or resubmit if needed Appeal with DOB verification and clinical documentation if the age-diagnosis combination is valid.
5. Follow up Monitor the claim status and take additional action as needed based on the COB determination.

Common RARC Pairings

The RARC code tells you exactly what triggered the OA-9:

How to Prevent OA-9

• Ensure accurate DOB across all payer submissions
• Validate age-diagnosis consistency for secondary claims

Also Filed As

The same CARC 9 may appear with different Group Codes:

Related Denial Codes