Keep tabs on points for diagnoses, OASIS answers. Calculating case mix points isn't as easy as it once was. The four equation model established in 2012 PPS adds a layer of complexity. But this table from Lisa Selman-Holman, JD, BSN, RN, HCS-D, COS-C, HCS-O, consultant and principal of Selman-Holman & Associates and CoDR -- Coding Done Right in Denton, Texas can help you track the case mix points you're due.