I’ve seen the previous post (and many discussions out there) about the problems with adjusting for post-baseline covariates in a pre-post ANCOVA analysis of treatment groups. Are there any issues or considerations for adjusting for baseline variables that will be effected by the treatment?
For example, say we are testing the effect of a low-dose vs high-dose statin on carotid intima media thickness (CIMT). We measure CIMT before treatment, and CIMT one year later. We also measure LDL-C at baseline. Would there be any issues in testing post-CIMT between groups, adjusted for pre-CIMT AND pre-LDL-C?
Thank you in advance!