Confidence interval for survival function

[Tristan Lorino <tristan.lorino@lcpc.fr>]

Hi,

I try to plot on the same graph three survival functions (KM, Weibull
and Cox) with their confidence intervals:

> weibfit_survReg(Surv(time,status)~1, data=Cens)
> coxfit <- coxph(Surv(time,status) ~ 1, data=Cens)
> x_seq(0,10,by=.3)
> plot(survfit(Surv(time,status), data=Cens),ylim=c(.4,1))
> points(survfit(coxfit), type="l",col=2)
> points(x,1-pweibull(x, 1/weibfit$scale, exp(coef(weibfit))),type="l",col=3)

Is there a simple way to obtain CI for Weibull and Cox survival
curves? Conf.type and conf.int options do not change the output.

Thanks in advance,

Tristan Lorino


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