Dear Allstat,
While reviewing several publications, I've noticed multivariate models where
a post-baseline efficacy variable has been added along with treatment to
analyse the effect on a change from baseline parameter. This has been done
in cases where one would want to check whether a measure taken early during
the study is a predictor of response for another variable later on.
I have reservations about the use of post baseline parameters in models
along with treatment and would much prefer seeing correlation analysis being
performed instead. I am however having problems explaining to
non-statisticians why this approach is inappropriate. Can anyone suggest
related papers on this topic or a suitable explanation on why this approach
is incorrect?
Thank you,
Colin
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