Medicare Compliance Review of John Muir Medical Center, Walnut Creek, for Calendar Years 2008 Through 2010

John Muir Medical Center, Walnut Creek (the Hospital), located in Walnut Creek, California, complied with Medicare billing requirements for 162 of the 197 inpatient and outpatient claims we reviewed. However, the Hospital did not fully comply with Medicare billing requirements for the remaining 35 claims, resulting in overpayments totaling $308,000 for calendar years 2008 through 2010. These overpayments occurred primarily because the Hospital's existing controls did not adequately prevent incorrect billing of these Medicare claims.