The Optional State Assessment (OSA) Item Set, OSA Manual, and OSA Change History table are now available in the Downloads section on the Minimum Data Set (MDS) 3.0 Resident Assessment Instrument (RAI) Manual page. The OSA is not a Federally required assessment; rather, it may be required in some States for payment purposes. Each state determines whether the OSA is required, and if so, when the assessment must be completed. For questions regarding completion of the OSA, please contact your State Survey Agency.