In 2024, the Office of Inspector General (OIG) found that health insurers added new — and questionable — diagnoses to 1.7 million Medicare Advantage (MA) members, generating approximately $7.5 billion in higher payments for those insurers.
For journalists, payments that raise questions from regulators translate into a major story because they can harm patients and Medicare itself. Such harm is especially important since Medicare Advantage insurers are believed to be significantly overpaid and under scrutiny for higher payments partly linked to manipulation of the risk-adjusted payment system, as the Center for Medicare Advocacy reported in 2024.
More than half of all Medicare beneficiaries (54%) were enrolled in Medicare Advantage plans as of last year. That enrollment level costs taxpayers about $83 billion annually, roughly 22% more than it costs to provide care in traditional Medicare, according to a report from the Leonard D. Schaeffer Institute for Public Policy & Government Service at USC.
“Diagnoses reported only on enrollees’ health-risk assessments (HRAs) and HRA-linked chart reviews, and not on any other 2022 service records, resulted in the higher payments,” the OIG noted. “The lack of any other follow-up visits, procedures, tests or supplies for these diagnoses in the MA encounter data for 1.7 million MA enrollees raises concerns.”
Either the $7.5 billion in payments was improper because the diagnoses were inaccurate, or the Medicare Advantage members did not get the care needed for their conditions reported only on HRAs or on reviews of patients’ charts, the OIG concluded.
The report was the tip of the iceberg
The health insurers did not support the need for higher payments with any documents beyond doing HRAs and reviewing patients’ medical charts in 2023, the OIG showed in its report to the federal Department of Health and Human Services, “Medicare Advantage: Questionable Use of Health Risk Assessments Continues To Drive Up Payments to Plans by Billions,” issued Oct. 21, 2024.
That OIG report was one of many on how UnitedHealth Group (UHG) and at least 20 other health insurers conducted HRAs and chart reviews, the OIG reported. The most recent report was a 104-page analysis that the U.S. Senate Finance Committee published on Jan. 12, “How UnitedHealth Group Puts the Risk in Medicare Advantage Risk Adjustment.” The report cited the work of multiple journalists, including a team of reporters from The Wall Street Journal, who have covered the story since 2022, as we reported on March 9. The Senate report also noted the work of a team from STAT News, who started reporting on the story in 2023, STATNews reporter Bob Herman said.
In a statement announcing the report, committee Chairman U.S. Sen. Chuck Grassley (R-Iowa) wrote that UnitedHealth Group, the nation’s largest health insurer, appeared “to be gaming the MA system, turning risk adjustment into its own business and siphoning off taxpayer money in breach of the program’s original intent.” The OIG report was based on more than 50,000 pages of documents UnitedHealth Group sent to Grassley.
While many journalists have covered the story, there are still multiple significant reporting angles to explore. Health insurers serving the Medicare Advantage program increasingly misuse HRAs and patients’ medical records to boost their revenue, the U.S. Senate report noted. “Taxpayers fund billions of dollars in overpayments to MA companies each year based on unsupported diagnoses for MA enrollees,” the report added. “Unsupported diagnoses inflate risk-adjusted payments and drive improper payments in the MA program.”
Multiple stories to cover
In addition to UnitedHealth Group’s involvement, the OIG noted that 20 Medicare Advantage insurers collected 80% of the estimated $7.5 billion in payments. In doing so, the Medicare Advantage companies generated a large share of payments resulting from HRAs or chart reviews for certain health conditions, including serious and chronic illnesses, such as diabetes and congestive heart failure, the report showed.
In 2024, for example, researchers writing in Health Affairs reported that health plans enhance Medicare Advantage members’ health risks by exaggerating coding intensity, thus adding or inflating MA members’ diagnoses. “One factor that may play a role in escalating coding intensity is HRAs — typically in-home reviews of enrollees’ health status,” they wrote.
The researchers also found that almost half (44.4%) of Medicare Advantage beneficiaries had at least one HRA and that among those members, their hierarchical condition category (HCC) scores increased by 12.8%, on average, as a result of using HRAs.
Other insurers benefit from UnitedHealth’s expertise
The Senate Finance Committee report cited four findings that could be useful to journalists.
- First, UnitedHealth Group has what the committee called “a robust diagnosis capture workforce” that includes health care providers and coders.
- Second, UnitedHealth Group uses “its advanced data assets and data analytics” to maximize its workforce’s ability to capture diagnoses, the report noted. Other Medicare Advantage insurers have adopted UHG’s methods to capture more diagnoses from Medicare Advantage members based on health risk assessments and chart reviews.
- Third, UnitedHealth Group works with other Medicare Advantage insurers to explain how it collects information to add diagnoses to patients’ records and how other insurers can do data mining and chart reviews, perform in-home HRAs and run pay-for-coding programs, the committee report noted.
- Fourth, other Medicare Advantage insurers can use the strategies that UnitedHealth Group employs to capture diagnoses to increase enrollees’ risk scores, including in-home HRAs, chart reviews, pay-for-coding programs and by acquiring physician groups, the report showed.
If, as the report noted, other health insurers have adopted these strategies from UnitedHealth Group, journalists may be able to find similar coding strategies as reporting teams from The Wall Street Journal and STAT News have done.
Resources
- Annual Wellness Visit Health Risk Assessment, Centers for Medicare Services, Feb. 11, 2026.
- Chart Reviews Increase Payments to Medicare Advantage Insurers for 1 in 6 Enrollees, Jeannie Fuglesten Biniek and others, KFF, Nov. 20, 2025.
- How UnitedHealth harnesses its physician empire to squeeze profits out of patients, Bob Herman, Tara Bannow, Casey Ross and Lizzy Lawrence for STAT News, July 25, 2024.
- Medicare Advantage Insurers Often Use Rewards and Incentives to Encourage Enrollees to Complete Health Risk Assessments (HRAs), Meredith Freed and others, KFF, April 28, 2025.
- Combining Patient Survey Data With Diagnosis Codes Improved Medicare Advantage Risk-Adjustment Accuracy, Meghan Bellerose and others, Health Affairs, January 2025.
- Medicare Advantage Costs Taxpayers 22% More Per Enrollee. Here’s How Payment Reform Could Help Close the Gap, The USC Leonard D. Schaeffer Institute for Public Policy & Government Service, Nov. 26, 2024.
- Insurers Pocketed $50 Billion From Medicare for Diseases No Doctor Treated, Christopher Weaver, Tom McGinty, Anna Wilde Mathews and Mark Maremont, The Wall Street Journal, July 8, 2024.
- In-Home Health Risk Assessments and Chart Reviews Contribute to Coding Intensity in Medicare Advantage, Paul D. Jacobs, Health Affairs, July 2024.
