We recommend that the contracting officer direct the Plan to perform a review of its paid claims on a routine basis (i.e., monthly, quarterly, and/or annually) to verify the accuracy of its COB processing. The Plan’s methodology for selecting claims to review should include consideration of those claims most likely to require COB (e.g., basic Class A services that include oral examinations, prophylaxis, diagnostic evaluations, sealants and x-rays.). The results of these reviews should be shared with OPM to identify error rates, causes of errors, performance improvements, and agreed-upon solutions to resolve problems.