See at a glance which diagnoses, OASIS answers earn points. It's not easy to calculate case mix points anymore. The four equation model in 2012 PPS makes this once-easy exercise a chore. But this chart 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.