Hi group,  I have a clinical dataset with about 80 patients. They had a baseline score (pre-intervention score) and a post intervention score. I used paired t test to compare the mean difference.  Now I need to get parameter estimate (coefficient) of the post score  in a linear model and possibly add multiple covariates in later.  To my knowledge,  I can't really use ANCOVA, because it requires post-score as the dependent variable, and pre-score as the predictor. I also thought of using the difference of pre-/post- score as the outcome, but i'm not sure what the predictor would be in that model.  I'm planning on using proc glm. So the code will be something like: "proc glm data=have; model difference= ? /clparam;" So in short, I want to test the effect of intervention in score. Thanks for any tips and helps!      ... View more