According to CMS, the Quality Measures (QMs) are calculated using information from the Minimum Data Set (MDS). The MDS is a national database created by CMS to collect information on the medical condition, need and functional level of every person who resides in a nursing home certified to participate in Medicare and Medicaid. Nursing home staff (including nurses, social workers and therapists) complete this information as part of a comprehensive assessment of each resident's functional capabilities and medical needs and the information is updated periodically according to CMS rules. These data are also used to determine payment. Although the data are self-reported by nursing homes, the State survey agency audits samples of MDS information for accuracy. Each facility transmits its MDS data to a central state data repository. The data are then sent on to CMS' centralized data repository. Before MDS data can be accepted by the state, all MDS submissions are subject to a system of automatic, computerized edits to make sure that the MDS data are coded correctly and adhere to CMS specifications. CMS will also audit and verify MDS assessments through a program safeguard contract that was recently awarded. The Data Assessment and Verification Contractor (DAVE) will provide ongoing centralized data surveillance to make sure the data are accurate and reliable.