interpretable models

From harrisof@capaccess.org Fri Jun 13 21:09:01 1997 Subject: interpretable models I really didn't mean adding another fitted parameter to the model. In typical clinical trials, especially the Phase III and IV variety I see more of myself, the gender ratio is not particularly related to the population ratio. Hence V=THETA(1)+THETA(2)*(WT-70) might be rather strange if 80% of the patients were of one gender, which is quite possible. My suggestion is that, where FLAG=1 for males and 0 for females, V=THETA(1)+THETA(2)*(WT-60-20*FLAG) where the constants "60" and "20" are chosen so 60+20*FLAG will yield the population means for each gender. In practice, clearance and volume of distribution can depend on gender in more complex and drug dependent ways, and whatever we know ought to be put to good use. I'm a statistician myself, and agree that estimation based on the data in hand is often best, but I'm always interested to learn what my medical colleagues regard as more readily interpretable. Elegant statistical results aren't worth much in my workplace if only statisticians can understand them.