I am trying to reverse code some variables in a 4-point likert scale. I do not want to include the missing variables, or those that said "I don't know" (98) or "Prefer not to answer" (99).   my code is set up like this:   data DISRUPT_likert1; set DISRUPT_likert; IF  (Q15_1 ne .) OR (Q15_1 ne 99) OR (Q15_1 ne 98) THEN Q15_1RC = 5-Q15_1; run;   It is still including 99 and 98. Can someone help me find why? ... View more