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Series: Medicare Advantage Risk-Adjustment Data - Targeted Review of Documentation Supporting Specific Diagnosis Codes

Announced on  | Last Modified on  | Series Number: W-00-24-35079
Status
Active
Agency
Centers for Medicare and Medicaid Services

OBJECTIVE

Payments to Medicare Advantage (MA) organizations are risk-adjusted on the basis of the health status of each beneficiary. 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 (SSA §§ 1853(a)(1)(C) and (a)(3)). In general, MA organizations receive higher payments for sicker patients. 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 determine whether the diagnoses submitted complied with Federal requirements.

There are 11 projects in this series.

Project titles will remain unpublished until projects are complete and reports are posted.

ACTIVE PROJECTS IN THIS SERIES (3)

Project A-07-22-01207 • Announced on Mar 21, 2022

Project A-07-22-01208 • Announced on Mar 21, 2022

Project A-03-22-00004 • Announced on Apr 25, 2022

COMPLETED PROJECTS IN THIS SERIES (8)

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Humana Health Benefit of Louisiana (Contract H1951) Submitted to CMS

Project A-06-21-02001 • Completed on December 8, 2025

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Coventry Health and Life Insurance Company (Contract H1608) Submitted to CMS

Project A-02-22-01020 • Completed on June 3, 2025

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That UCare Minnesota (Contract H2459) Submitted to CMS

Project A-07-22-01209 • Completed on December 23, 2024

Medicare Advantage Compliance Audit of Selected Diagnosis Codes That Blue Care Network of Michigan (Contract H5883) Submitted to CMS

Project A-06-20-02000 • Completed on December 20, 2024

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Triple-S Advantage, Inc., (Contract H5774) Submitted to CMS

Project A-04-21-07095 • Completed on December 19, 2024

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Humana Health Plan (Contract H2649) Submitted to CMS

Project A-02-22-01001 • Completed on September 23, 2024

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That HealthAssurance Pennsylvania, Inc (Contract H5522) Submitted to CMS

Project A-05-22-00020 • Completed on September 23, 2024

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Independent Health Association, Inc. (Contract H3362) Submitted to CMS

Project A-07-19-01194 • Completed on June 26, 2024

TIMELINE

  • September 9, 2019
    Series Number W-00-24-35079 Assigned
  • September 9, 2019
    Project Announced

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Independent Health Association, Inc. (Contract H3362) Submitted to CMS - A-07-19-01194

  • January 27, 2020
    Project Announced

    Medicare Advantage Compliance Audit of Selected Diagnosis Codes That Blue Care Network of Michigan (Contract H5883) Submitted to CMS - A-06-20-02000

  • January 18, 2021
    Project Announced

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Triple-S Advantage, Inc., (Contract H5774) Submitted to CMS - A-04-21-07095

  • September 27, 2021
    Project Announced

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Humana Health Benefit of Louisiana (Contract H1951) Submitted to CMS - A-06-21-02001

  • October 1, 2021
    Project Announced

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Humana Health Plan (Contract H2649) Submitted to CMS - A-02-22-01001

  • March 21, 2022
    Projects Announced

    Project A-07-22-01207

  • Project A-07-22-01208

  • April 13, 2022
    Project Announced

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That UCare Minnesota (Contract H2459) Submitted to CMS - A-07-22-01209

  • April 25, 2022
    Project Announced

    Project A-03-22-00004

  • June 8, 2022
    Project Announced

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That HealthAssurance Pennsylvania, Inc (Contract H5522) Submitted to CMS - A-05-22-00020

  • July 25, 2022
    Project Announced

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Coventry Health and Life Insurance Company (Contract H1608) Submitted to CMS - A-02-22-01020

  • June 26, 2024
    Project Complete - A-07-19-01194

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Independent Health Association, Inc. (Contract H3362) Submitted to CMS has been marked as complete. This audit resulted in 3 recommendations.

  • September 23, 2024
    Project Complete - A-02-22-01001

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Humana Health Plan (Contract H2649) Submitted to CMS has been marked as complete. This audit resulted in 3 recommendations.

  • September 23, 2024
    Project Complete - A-05-22-00020

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That HealthAssurance Pennsylvania, Inc (Contract H5522) Submitted to CMS has been marked as complete. This audit resulted in 3 recommendations.

  • December 19, 2024
    Project Complete - A-04-21-07095

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Triple-S Advantage, Inc., (Contract H5774) Submitted to CMS has been marked as complete. This audit resulted in 3 recommendations.

  • December 20, 2024
    Project Complete - A-06-20-02000

    Medicare Advantage Compliance Audit of Selected Diagnosis Codes That Blue Care Network of Michigan (Contract H5883) Submitted to CMS has been marked as complete. This audit resulted in 3 recommendations.

  • December 23, 2024
    Project Complete - A-07-22-01209

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That UCare Minnesota (Contract H2459) Submitted to CMS has been marked as complete. This audit resulted in 3 recommendations.

  • June 3, 2025
    Project Complete - A-02-22-01020

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Coventry Health and Life Insurance Company (Contract H1608) Submitted to CMS has been marked as complete. This audit resulted in 3 recommendations.

  • December 8, 2025
    Project Complete - A-06-21-02001

    Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Humana Health Benefit of Louisiana (Contract H1951) Submitted to CMS has been marked as complete. This audit resulted in 3 recommendations.

  • Today
    3 Audits In-Progress
  • Est FY2026
    Estimated Fiscal Year for Series Completion

8 REPORT PUBLISHED

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Humana Health Plan, Inc. (Contract H2649) Submitted to CMS (A-02-22-01001)

24-A-02-107.01 to CMS - Open Unimplemented
Update expected on 03/15/2026
We recommend that Humana Health Plan, Inc. refund to the Federal Government the $6,777,385 of estimated overpayments.

24-A-02-107.02 to CMS - Open Unimplemented
Update expected on 03/15/2026
We recommend that Humana Health Plan, Inc. identify, for the high-risk diagnoses included in this report, similar instances of noncompliance that occurred before or after our audit period and refund any resulting overpayments to the Federal Government.

24-A-02-107.03 to CMS - Open Unimplemented
Update expected on 03/15/2026
We recommend that Humana Health Plan, Inc. continue to examine its existing compliance procedures to identify areas where improvements can be made to ensure that diagnosis codes that are at high risk for being miscoded comply with Federal requirements (when submitted to CMS for use in CMS's risk adjustment program) and take the necessary steps to enhance those procedures.

View in Recommendation Tracker

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Coventry Health and Life Insurance Company (Contract H1608) Submitted to CMS (A-02-22-01020)

25-A-02-069.01 to CMS - Open Unimplemented
Update expected on 03/15/2026
We recommend that Coventry Health and Life Insurance Company refund to the Federal Government the $6,995,522 of estimated net overpayments.

25-A-02-069.02 to CMS - Open Unimplemented
Update expected on 03/15/2026
We recommend that Coventry Health and Life Insurance Company identify, for the high-risk diagnoses included in this report, similar instances of noncompliance that occurred after our audit period and refund any resulting overpayments to the Federal Government.

25-A-02-069.03 to CMS - Open Unimplemented
Update expected on 03/15/2026
We recommend that Coventry Health and Life Insurance Company continue to examine its existing compliance procedures to identify areas where improvements can be made to ensure that diagnosis codes that are at high risk for being miscoded comply with Federal requirements (when submitted to CMS for use in CMS's risk adjustment program) and take the necessary steps to enhance those procedures.

View in Recommendation Tracker

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Triple-S Advantage, Inc., (Contract H5774) Submitted to CMS (A-04-21-07095)

25-A-04-030.01 to CMS - Open Unimplemented
Update expected on 03/30/2026
We recommend that Triple-S Advantage, Inc. refund to the Federal Government $296,758 in net overpayments.

25-A-04-030.02 to CMS - Open Unimplemented
Update expected on 03/30/2026
We recommend that Triple-S Advantage, Inc. identify, for the high-risk diagnoses included in this report, similar instances of noncompliance that occurred before or after our audit period and refund any resulting overpayments to the Federal Government.

25-A-04-030.03 to CMS - Open Unimplemented
Update expected on 03/30/2026
We recommend that Triple-S Advantage, Inc. continue to examine its existing compliance procedures to identify areas where improvements can be made to ensure that diagnosis codes that are at high risk of being miscoded comply with Federal requirements (when submitted to CMS for use in CMS's risk adjustment program) and take the necessary steps to enhance those procedures.

View in Recommendation Tracker

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That HealthAssurance, Pennsylvania, Inc. (Contract H5522) Submitted to CMS (A-05-22-00020)

24-A-05-106.01 to CMS - Open Unimplemented
Update expected on 03/15/2026
We recommend that CVS Health refund to the Federal Government the $4,256,568 of estimated overpayments.

24-A-05-106.02 to CMS - Open Unimplemented
Update expected on 03/15/2026
We recommend that CVS Health identify, for the high-risk diagnoses included in this report, similar instances of noncompliance that occurred before or after our audit period and refund any resulting overpayments to the Federal Government.

24-A-05-106.03 to CMS - Open Unimplemented
Update expected on 03/15/2026
We recommend that CVS Health continue its examination of its existing compliance procedures to identify areas where improvements can be made to ensure that diagnosis codes that are at high risk for being miscoded comply with Federal requirements (when submitted to CMS for use in CMS's risk adjustment program) and take the necessary steps to enhance those procedures.

View in Recommendation Tracker

Medicare Advantage Compliance Audit of Specific Diagnosis Codes Blue Care Network of Michigan (Contract H5883) Submitted to CMS (A-06-20-02000)

25-A-06-033.01 to CMS - Open Unimplemented
Update expected on 03/24/2026
We recommend that Blue Care Network of Michigan refund to the Federal Government the $3,412,369 of estimated overpayments.

25-A-06-033.02 to CMS - Open Unimplemented
Update expected on 03/24/2026
We recommend that Blue Care Network of Michigan identify, for the high-risk diagnoses included in this report, similar instances of noncompliance that occurred before or after our audit period and refund any resulting overpayments to the Federal Government.

25-A-06-033.03 to CMS - Open Unimplemented
Update expected on 03/24/2026
We recommend that Blue Care Network of Michigan continue to examine its existing compliance procedures to identify areas where improvements can be made to ensure that diagnosis codes that are at high risk for being miscoded comply with Federal requirements (when submitted to CMS for use in CMS's risk adjustment program) and take the necessary steps to enhance those procedures.

View in Recommendation Tracker

Medicare Advantage Compliance Audit of Specific Diagnosis Codes Humana Health Benefit of Louisiana (Contract H1951) Submitted to CMS (A-06-21-02001)

Most of the selected diagnosis codes that Humana submitted to CMS for use in CMS’s risk adjustment program did not comply with Federal requirements.

  • For 218 of the 240 sampled enrollee-years, medical records did not support the diagnosis codes and resulted in $553,049 in overpayments.
  • On the basis of our sample results, we estimated that Humana received at least $10.5 million in overpayments for 2017 and 2018.

As demonstrated by the errors found in our sample, Humana’s policies and procedures to prevent, detect, and correct noncompliance with CMS’s program requirements, as mandated by Federal regulations, could be improved. Due to Federal regulations that limit the use of extrapolation for recovery purposes to 2018 and forward, we limited our recommended recovery to $5.5 million.

26-A-06-020.01 to CMS - Open Unimplemented
Update expected on 06/07/2026
We recommend that Humana Health Benefit of Louisiana refund to the Federal Government the $5,470,725 of estimated overpayments.

26-A-06-020.02 to CMS - Open Unimplemented
Update expected on 06/07/2026
We recommend that Humana Health Benefit of Louisiana identify, for the high-risk diagnoses included in this report, similar instances of noncompliance that occurred after our audit period and refund any resulting overpayments to the Federal Government.

26-A-06-020.03 to CMS - Open Unimplemented
Update expected on 06/07/2026
We recommend that Humana Health Benefit of Louisiana continue to examine its existing compliance procedures to identify areas where improvements can be made to ensure that diagnoses that are at high risk for being miscoded comply with Federal requirements (when submitted to CMS for use in CMS's risk adjustment program) and take the necessary steps to enhance those procedures.

View in Recommendation Tracker

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Independent Health Association, Inc. (Contract H3362) Submitted to CMS (A-07-19-01194)

24-A-07-085.01 to CMS - Open Unimplemented
Update expected on 04/01/2026
We recommend that Independent Health Association, Inc. refund to the Federal Government the $646,217 of overpayments.

24-A-07-085.02 to CMS - Open Unimplemented
Update expected on 04/01/2026
We recommend that Independent Health Association, Inc. identify, for the high-risk diagnoses included in this report, similar instances of noncompliance that occurred before and after our audit period and refund any resulting overpayments to the Federal Government.

24-A-07-085.03 to CMS - Open Unimplemented
Update expected on 04/01/2026
We recommend that Independent Health Association, Inc. continue its examination of its existing compliance procedures to identify areas where improvements can be made to ensure that diagnosis codes that are at high risk for being miscoded comply with Federal requirements (when submitted to CMS for use in CMS's risk adjustment program) and take the necessary steps to enhance those procedures.

View in Recommendation Tracker

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That UCare Minnesota (Contract H2459) Submitted to CMS (A-07-22-01209)

25-A-07-034.01 to CMS - Open Unimplemented
Update expected on 03/15/2026
We recommend that UCare Minnesota refund to the Federal Government the $4,761,271 of estimated net overpayments.

25-A-07-034.02 to CMS - Open Unimplemented
Update expected on 03/15/2026
We recommend that UCare Minnesota identify, for the high-risk diagnoses included in this report, similar instances of noncompliance that occurred before or after our audit period and refund any resulting overpayments to the Federal Government.

25-A-07-034.03 to CMS - Open Unimplemented
Update expected on 03/15/2026
We recommend that UCare Minnesota continue its examination of its existing compliance procedures to identify areas where improvements can be made to ensure that diagnoses that are at high risk for being miscoded comply with Federal requirements (when submitted to CMS for use in CMS's risk adjustment program) and take the necessary steps to enhance those procedures.

View in Recommendation Tracker
Work Plan Type
Office of Audit Services
HHS Agencies
Centers for Medicare and Medicaid Services
Issue Areas
Contracts Financial Stewardship Managed Care
Target Groups
Elderly
Financial Groups
Medicare C