In 2006, the Centers for Medicare & Medicaid Services limited insurance coverage of weight loss surgery to hospitals considered centers of excellence. Now a study finds there is no significant difference between centers of excellence and other hospitals in the rate and severity of surgery-related complications and the need for repeat surgeries.

Researchers at the University of Michigan and Weill Cornell Medical College in New York looked at data on more than 20,000 Medicare patients who underwent bariatric surgery between 2004 and 2009, before and after the policy. Researchers then compared the data to outcomes for more than 200,000 non-Medicare patients. They found that complications from surgery declined similarly in both groups.