Beta This is a new resource
-

                    your [feedback]() will help us improve it.

---

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

Announced on

09/09/2019

| Last Modified on

03/10/2026

| 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Project titles will remain unpublished until projects are complete and reports are posted.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 (2)

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 (9)

Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Blue Cross Blue Shield of Alabama (Contract H0104) Submitted to CMS

Project A-07-22-01207 • Completed on March 10, 2026

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 Risk-Adjustment Data - Targeted Review of Documentation Supporting Specific Diagnosis Codes - Audit 2

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

Medicare Advantage Risk-Adjustment Data - Targeted Review of Documentation Supporting Specific Diagnosis Codes - Audit 11

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 Risk-Adjustment Data - Targeted Review of Documentation Supporting Specific Diagnosis Codes - Audit 4

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 Risk-Adjustment Data - Targeted Review of Documentation Supporting Specific Diagnosis Codes - Audit 8

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 Risk-Adjustment Data - Targeted Review of Documentation Supporting Specific Diagnosis Codes - Audit 8 - 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 Risk-Adjustment Data - Targeted Review of Documentation Supporting Specific Diagnosis Codes - Audit 4 - 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 Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Blue Cross Blue Shield of Alabama (Contract H0104) Submitted to CMS - A-07-22-01207
• Project A-07-22-01208
• April 13, 2022 Project Announced Medicare Advantage Risk-Adjustment Data - Targeted Review of Documentation Supporting Specific Diagnosis Codes - Audit 11 - 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 Risk-Adjustment Data - Targeted Review of Documentation Supporting Specific Diagnosis Codes - Audit 2 - A-02-22-01020
• June 26, 2024 Project Complete - A-07-19-01194 Medicare Advantage Risk-Adjustment Data - Targeted Review of Documentation Supporting Specific Diagnosis Codes - Audit 8 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.
• 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.
• December 19, 2024 Project Complete - A-04-21-07095 Medicare Advantage Risk-Adjustment Data - Targeted Review of Documentation Supporting Specific Diagnosis Codes - Audit 4 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 Risk-Adjustment Data - Targeted Review of Documentation Supporting Specific Diagnosis Codes - Audit 11 has been marked as complete. This audit resulted in 3 recommendations.
• June 3, 2025 Project Complete - A-02-22-01020 Medicare Advantage Risk-Adjustment Data - Targeted Review of Documentation Supporting Specific Diagnosis Codes - Audit 2 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.
• March 10, 2026 Project Complete - A-07-22-01207 Medicare Advantage Compliance Audit of Specific Diagnosis Codes That Blue Cross Blue Shield of Alabama (Contract H0104) Submitted to CMS complete. Report Published
• Today 2 Projects In-Progress
• Est FY2026 Estimated Fiscal Year for Series Completion

9 REPORT PUBLISHED

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

Recommendation Details (3)

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 That Humana Health Plan, Inc. (Contract H2649) Submitted to CMS (A-02-22-01001)

Recommendation Details (3)

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)

Recommendation Details (3)

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 Blue Care Network of Michigan (Contract H5883) Submitted to CMS (A-06-20-02000)

Recommendation Details (3)

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.

Recommendation Details (3)

26-A-06-020.01 to CMS - Open Unimplemented Update expected on
07/14/2026 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
07/14/2026 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
07/14/2026 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 Triple-S Advantage, Inc., (Contract H5774) Submitted to CMS (A-04-21-07095)

Recommendation Details (3)

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 Independent Health Association, Inc. (Contract H3362) Submitted to CMS (A-07-19-01194)

Recommendation Details (3)

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 Blue Cross and Blue Shield of Alabama (Contract H0104) Submitted to CMS (A-07-22-01207) Most of the selected diagnosis codes that BCBSAL submitted to CMS for use in CMS’s risk adjustment program did not comply with Federal requirements.

• For 247 of the 271 sampled enrollee-years, medical records did not support the diagnosis codes and resulted in $769,195 in overpayments.
• On the basis of our sample results, we estimated that BCBSAL received at least $7 million in overpayments for 2018 and 2019. As demonstrated by the errors found in our sample, BCBSAL’s policies and procedures to prevent, detect, and correct noncompliance with CMS’s program requirements, as mandated by Federal regulations, could be improved.

Recommendations are updated each month and may not immediately be available for recently completed projects. #### Medicare Advantage Compliance Audit of Specific Diagnosis Codes That UCare Minnesota (Contract H2459) Submitted to CMS (A-07-22-01209)

Recommendation Details (3)

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