search for: edtrt

Hello, I wonder when I do coxph in R: coxph( Surv(start, stop, event) ~ x, data=test) If x is a categorical varible (1,2,3,4,5), should I creat four dummy varibles for it? if yes, how can I get the overall p value on x other than for each dummy variable? Thanks Lisa Wang Princess Margaret Hospital Phone 416 946 4501

...rs=0,stage=0,status=0,treatmnt=0, triglyc=0,urinecu=0)) fit<-coxph(Surv(obstime,status)~bili+edmadj+albumin+protime+age,data=liver) summary(fit) ----------------- End of code but the answer is rather different from that in the book (p.688 - for anyone with the book). The book refers to EDTRT, but the dataset has EDMADJ and EDMEMA, also the book talks about 312 patients and the dataset has 418 lines. Has anybody else used this dataset? Cheers, Geoff Russell

Hello, I am trying to find an R function to compute 'direct adjusted survival' with standard errors. A SAS-macro to do this is presented in Zhang X, Loberiza FR, Klein JP, Zhang MJ. A SAS macro for estimation of direct adjusted survival curves based on a stratified Cox regression model. Comput Methods Programs Biomed 2007;88:95-101. It appears that this method is not implemented in R.