Hi Geoff, I think the answer to such a problem (overall survival vs. disease free survival) depends on the regulatory environment, for example, in a phase III clinical trial, OS would be used, whereas in an equivalence study, DFS would be used.
Best, Matthias Geoff Russell schrieb: > Dear UseRs, > > Suppose I have data regarding smoking habits of a prospective cohort and wish > to determine the risk ratio of colorectal cancer in the smokers compared to > the non-smokers. What do I do at the end of the study with people who die > of heart disease? Can I just censor them exactly the same as people who become > uncontactable or who die in a plane crash? If not, why not? > > I'm thinking that heart disease isn't independent of smoking even though > a death from heart disease is probably uninformative about colorectal > cancer risk. Hence > I suspect simply censoring these deaths will introduce a bias, but I don't > know > how to correct for it. > > Many thanks, > > Geoff Russell -- an interested student > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
