Dear Colleagues

How do you approach the baseline levels in a design with two measurements? I have two randomly assigned groups, drug and placebo (subject effects) and two resting states pre and post intervention (conditions). If I am interested in the interaction “drug>placebo, post>pre” [1 -1] [1 -1], is there any way to set the contrasts to consider the significant interactions, which are not driven by baseline differences?

All your comments are highly appreciated,
Lucas