General question on modeling

Interesting topic. I have little to add to what has been presented already except to state that we are unlikely to come to a consensus regarding best practices on modeling, with or without FDA input. Statistians have been arguing over these very same issues in the linear regression world for decades and are at the same place we are. I would agree with Pete that in general, covariate analysis adds very little to most analyses. It was my naive hope a few years ago that pharmacogenomics would bring us better covariates which would explain more variability in drug PK and response. I am older now, (and more jaded) and am increasingly uncertain as to whether PG will bring us anything usable, despite glowing articles in Time and Newsweek about "personalized medicine". Mike Fossler