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Medicare Part C Audits of Documentation Supporting Specific Diagnosis Codes

Payments to Medicare Advantage (MA) organizations are risk-adjusted based on each enrollee's health status (SSA § 1853(a)). MA organizations are required to submit risk-adjustment data to CMS in accordance with CMS instructions (42 CFR § 422.310(b)), and inaccurate diagnoses may cause CMS to pay MA organizations improper amounts. In general, MA organizations receive higher payments for enrollees with more complex diagnoses. CMS estimates that 9.5 percent of payments to MA organizations are improper, mainly due to unsupported diagnoses submitted by MA organizations. Prior OIG reviews have shown that some diagnoses are more at risk than others to be unsupported by medical record documentation. We will perform a targeted review of these diagnoses and will review the medical record documentation to ensure that it supports the diagnoses that MA organizations submitted to CMS for use in CMS's risk score calculations and to determine whether the diagnoses submitted complied with Federal requirements.

Announced or Revised Agency Title Component Report Number(s) Expected Issue Date (FY)
November 2023 Centers for Medicare and Medicaid Services Medicare Part C Audits of Documentation Supporting Specific Diagnosis Codes Office of Audit Services WA-24-0004 (W-00-24-35906) 2026