Careful audits of a representative sampling of bills from 37 Medicare Advantage Programs in 2007 have revealed some consistent patterns in the way they overbill, a Center for Public Integrity investigation finds. Nick Shepherd/Ikon Images/Getty Images hide caption

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Nick Shepherd/Ikon Images/Getty Images

The Centers for Medicare and Medicaid Services has spent about $117 million on Medicare Advantage audits that have recouped just $14 million related to overcharging. Jay Mallin/Bloomberg via Getty Images hide caption

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Jay Mallin/Bloomberg via Getty Images

Eliza Catchings worried when she got a letter from her Medicare Advantage plan saying she would have to pick a new doctor because of changes to the network. Courtesy of Jen Tayabji/Champaign County Health Care Consumers hide caption

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Courtesy of Jen Tayabji/Champaign County Health Care Consumers

A federal whistleblower suit unsealed in late February alleges that Humana knew about billing fraud involving Medicare Advantage patients and didn't stop it. Ty Wright/Bloomberg via Getty Images hide caption

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Ty Wright/Bloomberg via Getty Images

In a previously unreleased letter, Office of Management and Budget Director Shaun Donovan told the Dept. of Health and Human Services to devise an action plan for reducing wasteful Medicare and Medicaid payments. Gary Cameron/Reuters/Landov hide caption

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Gary Cameron/Reuters/Landov

A Texas lawsuit filed against 30 insurance plans in 15 states alleges that the companies overcharged Medicare for doctors' house calls. Laughing Stock/Corbis hide caption

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Laughing Stock/Corbis

Sen. Chuck Grassley has questions about what the feds are doing to investigate allegations of Medicare Advantage fraud. Drew Angerer/Getty Images hide caption

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Drew Angerer/Getty Images

Carol Berman, of West Palm Beach, Fla., makes the case for policymakers to protect Medicare Advantage benefits during the Coalition for Medicare Choices' Medicare Advantage Food Truck stop in Washington, D.C., on Monday. Bill Clark/CQ-Roll Call/Getty Images hide caption

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Bill Clark/CQ-Roll Call/Getty Images

Medicare beneficiaries who want to switch drug plans will have to make a decision earlier than usual this year.

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