The Government Accounting Office (GAO) has had ongoing concerns about the integrity of the Medicaid program due to its size, diversity, and recent rapid growth as a result of the Affordable Care Act. It is the second largest health insurance program in the U.S. based on expenditures ($576 billion combined federal and state spending projected for 2016). At the request of the Senate Finance Committee, the GAO reviewed and issued a report on its examination of CMS’s oversight and support of states’ Medicaid program integrity efforts.

The GAO found that CMS has improved its oversight and support of the states’ Medicaid program integrity needs and efforts through training initiatives and review and collaborative audit programs. In fact, collaborative audits identified substantial potential Medicaid overpayments to health care providers in recent years, with identified overpayments increasing from $2 million in fiscal year 2012 to $36 million in fiscal year 2015. The GAO contends, however, that improvements are still needed. The GAO concluded, and CMS agreed, that CMS should work with states on addressing barriers that improve state participation in collaborative audits, improve communication during audits, continue offering training programs, and develop systematic approaches to collecting and communicating promising state program integrity practices.