送交者: blackbox 于 2006-2-08, 17:19:33:
回答: don't be misled by blackbox, this study is important by its own merits 由 xj 于 2006-2-08, 16:12:29:
from this study. I have no question about the study design. A biologically risk may not equally have impact on certain groups of population. That is why the effect modification is one of key elements needed to be addressed when conducting an epidemiologic study.