A report by the Department of Health and Human Services Office of the Inspector General found that many Medicare Advantage and Medicaid managed care plans offer access to a limited proportion of behavioral health providers, and inaccurately list 72% of in-network behavioral health care providers as being available. Networks with high proportions of such providers that should not be listed are referred to as "ghost networks," which may include providers that have retired or changed locations. OIG recommended administrators use data to monitor provider networks and confirm the status of providers in a plan directory. The report also recommended the Centers for Medicare & Medicaid Services to continue exploring the creation of a national directory of behavioral health providers and listing which Medicare and Medicaid plans are accepted by each.