Simulation of Piecewise constant hazard models with two causes (Cox).

Source: R/sim-pc-hazard.R

Simulates data from piecwise constant baseline hazard that can also be of Cox type. Censor data at highest value of the break points for either of the cumulatives.

rcrisk(cumhaz1, cumhaz2, rr1, rr2, n = NULL, cens = NULL, rrc = NULL, ...)

Arguments

cumhaz1

cumulative hazard of cause 1

cumhaz2

cumulative hazard of cause 1

rr1

number of simulations or vector of relative risk for simuations.

rr2

number of simulations or vector of relative risk for simuations.

n

number of simulation if rr not given

cens

to censor further , rate or cumumlative hazard

rrc

retlativ risk for censoring.

...

arguments for rchaz

Author

Thomas Scheike

Examples

library(mets); data(bmt); library(survival)

cox1 <- phreg(Surv(time,cause==1)~tcell+platelet,data=bmt)
cox2 <- phreg(Surv(time,cause==2)~tcell+platelet,data=bmt)

X1 <- bmt[,c("tcell","platelet")]
n <- 100
xid <- sample(1:nrow(X1),n,replace=TRUE)
Z1 <- X1[xid,]
Z2 <- X1[xid,]
rr1 <- exp(as.matrix(Z1) %*% cox1$coef)
rr2 <- exp(as.matrix(Z2) %*% cox2$coef)

d <-  rcrisk(cox1$cum,cox2$cum,rr1,rr2)
dd <- cbind(d,Z1)

scox1 <- phreg(Surv(time,status==1)~tcell+platelet,data=dd)
scox2 <- phreg(Surv(time,status==2)~tcell+platelet,data=dd)
par(mfrow=c(1,2))
plot(cox1); plot(scox1,add=TRUE)
plot(cox2); plot(scox2,add=TRUE)

cbind(cox1$coef,scox1$coef,cox2$coef,scox2$coef)
#>                [,1]       [,2]       [,3]      [,4]
#> tcell    -0.4232606  0.3916056  0.3991068  1.077627
#> platelet -0.5654438 -1.1248031 -0.2461474 -1.014975