R Under development (unstable) (2024-12-12 r87438 ucrt) -- "Unsuffered Consequences" Copyright (C) 2024 The R Foundation for Statistical Computing Platform: x86_64-w64-mingw32/x64 R is free software and comes with ABSOLUTELY NO WARRANTY. You are welcome to redistribute it under certain conditions. Type 'license()' or 'licence()' for distribution details. R is a collaborative project with many contributors. Type 'contributors()' for more information and 'citation()' on how to cite R or R packages in publications. Type 'demo()' for some demos, 'help()' for on-line help, or 'help.start()' for an HTML browser interface to help. Type 'q()' to quit R. > library(survival) > # > # check of the Surv2 function > # > # Build a flat form of the mgus2 data set. Mix up the data set order, to test > # out that part of the underlying code. > set.seed(1953) > m2 <- mgus2[sample(1:nrow(mgus2), nrow(mgus2),replace=FALSE),] > > temp1 <- data.frame(m2[,1:7], ftime=0) > temp2 <- with(subset(m2, pstat==1), + data.frame(id=id, ftime=ptime, event="progression")) > > # competing risks: use only the first of death and progression > temp3 <- with(subset(m2, pstat==0), + data.frame(id=id, ftime=futime, + event=ifelse(death==0, "censor", "death"))) > mflat <- merge(temp1, rbind(temp2, temp3), all=TRUE) > mflat$event <- factor(mflat$event, c("censor", "progression", "death")) > > sfit1 <- survfit(Surv2(ftime, event) ~ sex, mflat, id=id) > > # now compare it to the usual way > etime <- with(mgus2, ifelse(pstat==1, ptime, futime)) > estat <- with(mgus2, ifelse(pstat==1, 1, 2*death)) > estat <- factor(estat, 0:2, c("censor", "progression", "death")) > sfit2 <- survfit(Surv(etime, estat) ~ sex, mgus2) > > all.equal(sfit1$pstate, sfit2$pstate) [1] TRUE > > # Cox model > cfit1 <- coxph(Surv2(ftime, event) ~ sex + age, data=mflat, id=id) > cfit2 <- coxph(Surv(etime, estat) ~ sex + age, data=mgus2, id=id) > all.equal(cfit1[c("coefficients", "var", "loglik", "score")], + cfit2[c("coefficients", "var", "loglik", "score")]) [1] TRUE > > # And using the explicit call to build a data set > sdata <- Surv2data(Surv2(ftime, event) ~ ., data=mflat, id=id) > cfit3 <- coxph(Surv2.y ~ sex + age, data=sdata, id=id) > all.equal(cfit1[c("coefficients", "var", "loglik", "score")], + cfit3[c("coefficients", "var", "loglik", "score")]) [1] TRUE > > # Create a data set with error = two events on the same day > # A model with this data will generate an error. > temp4 <- with(m2, + data.frame(id=id, ftime=futime, + event=ifelse(death==0, "censor", "death"))) > mflat2 <- merge(temp1, rbind(temp2, temp4), all=TRUE) > mflat2$event <- factor(mflat2$event, c("censor", "prog", "death")) > stemp <- survcheck(Surv2(ftime, event) ~ sex, data=mflat2, id=id) > all.equal(stemp$duplicate$row, which(duplicated(mflat2[,c("id", "ftime")]))) [1] TRUE > > # Full 3 state model. We need to make progressions that are tied with > # deaths be just a bit sooner. > temp2b <- with(subset(m2, pstat==1), + data.frame(id=id, ftime= ifelse(ptime==futime & death==1, ptime-.1, ptime), + event="progression")) > temp3b <- with(m2, + data.frame(id=id, ftime=futime, event=ifelse(death==0, "censor", "death"))) > > mflat3 <- merge(temp1, rbind(temp2b, temp3b), all=TRUE) > mflat3$event <- factor(mflat3$event, c("censor", "progression", "death")) > > cfit4 <- coxph(Surv2(ftime, event) ~ sex + age + mspike, mflat3, id=id) > > # For a standard start-stop data set use tmerge > m3 <- tmerge(m2[,1:7], subset(m2,,c(id, futime, death)), id=id, + event= event(futime, 2*death)) > m3 <- tmerge(m3, temp2b, id=id, event= event(ftime)) > m3$event <- factor(m3$event, 0:2, c("censor", "progression", "death")) > cfit5 <- coxph(Surv(tstart, tstop, event) ~ sex + age + mspike, m3, id=id) > > all.equal(cfit4[c("coefficients", "var", "loglik", "score")], + cfit5[c("coefficients", "var", "loglik", "score")]) [1] TRUE > > > proc.time() user system elapsed 1.17 0.09 1.25