Medicaid: Data Sets Provide Inconsistent Picture of Expenditures

On October 29, 2012, the U.S. Government Accountability Office (GAO) released a study comparing the two CMS data sets that report state Medicaid expenditures: 1)the MSIS data set, and 2) the CMS-64 data set. The MSIS data set is designed to report individual beneficiary claims data; and the CMS-64 data set aggregates states’ expenditures for reimbursement to states for their Medicaid expenditures. Neither data set provides a complete picture of Medicaid expenditures. The GAO report: 1) examines the extent to which MSIS and CMS-64 expenditure data differ, and (2) where possible, quantifies the identified differences . . .