CMS has awarded contracts to review the medical necessity of long term care hospital (LTCHs) stays, as authorized by the Medicare, Medicaid and SCHIP Extension Act of 2007 (MMSEA). Specifically, CMS has awarded contracts to AdvanceMed to perform LTCH sampling and validation, and to Wisconsin Physician Services (WPS) to perform medical review of LTCH claims to determine a national error rate for LTCHs. WPS will use existing inpatient hospital review criteria in order to determine the medical necessity of admission. CMS expects the medical reviews, which are scheduled to begin in January 2009, to help contractors to recover overpayments and determine if additional review is necessary.