Dear Prof. Broström, I have searched in the reference manual inside the package eha, updated recently. I did not find any description on how to enter id in the aftreg function except the description of the argument. Can you refer to a specific part of the manual? Do you mean another documentation?
I had also visited the posting guide before ( I included an example and all the details I could.). What else can I add? And have also read a a book intruducing survival analysis in R, but the doubt that I have is very specific to R computation. I reask the questions: I have a doubt on how to perform a weibull parametric survival anayisis using time-dependent covariates in R using both accelerated failure time(AFT) and proportional hazard (PH). I would highly appreciate a reply to my questions. I provide an example similar to data i use. (Here there are only two covariates one dependent and another independent) Data S sta time TDC1 total_time TIC1 ID A 1 0 1 48.50 1 1 1 B 0 0 1 65.96 2 1 2 B 1 1 2 65.08 2 1 2 C 0 0 1 0.00 2 4 3 C 1 1 2 0.00 2 4 3 D 0 0 1 72.74 2 5 4 D 1 1 2 72.52 2 5 4 E 0 0 1 61.84 2 3 5 E 0 1 2 60.56 2 3 5 F 0 0 1 35.04 4 2 6 F 0 1 2 36.97 4 2 6 F 0 2 3 37.92 4 2 6 F 1 3 4 39.01 4 2 6 time - time to event sta - starting time TDC - time dependent covariates TIC - time independent covariate total_time - total time at risk ID - ID Doubts: -AFT and PH time-dependent Weibull distribution I have tried to estimate an accelerated failure time(AFT) and proportional hazard (PH) parametric survival model with time-independent and time-dependent covariates with a weibull distribution. For that purpose, I have used the eha package. To my knowledge, the survival package does not provide a solution for estimating models with time-dependent models. weibullph <- phreg(Surv(sta,time,S) ~ TDC1 + TIC1, dist="weibull", data.frame=Data) weibullaft<-aftreg(Surv(sta,time,S) ~ TDC1 + TIC1, dist="weibull", data.frame=Data) ## aftreg gives an error when I add an ID argument... That should be used for controlling for time-varying variables. Error in aftreg.fit(X, Y, dist, strats, offset, init, shape, id, control, : *Overlapping intervals for id 2 * >From help(aftreg): id If there are more than one spell per individual, it is essential to keep spells together by the id argument. This allows for time-varying covariates. Here are the questions I have: 1- How can I solve this error? 2- Does the phreg function need an ID? Can I use it to estimate a model with time-dependent covariates? 3- How can time-dependent covariates be estimated with phreg or aftreg, or other function in R? Thank you very much, J -- View this message in context: http://r.789695.n4.nabble.com/AFT-model-time-dependent-with-weibull-distribution-tp3755079p3756424.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.
