Displaying 1 result from an estimated 1 matches for "timeplusag".
Did you mean:
timeplusage
2007 Feb 05
2
Two ways to deal with age in Cox model
...status=c(1,NA,1,0,1,1,0),
age= c(0, 2,1,1,1,0,0),
riskfactor= c(0, 0,0,0,1,1,1))
fitagecovariate<-coxph( Surv(time, status) ~ age +riskfactor, test1)
fitagecovariate
Age included as part of follow-up time:
test2<-test1
test2$timeplusage<-test2$time+test2$age
fitagefollowup<-coxph( Surv(timeplusage, status) ~ riskfactor, test2)
fitagefollowup
I would appreciate any thoughts about the differences in the
interpretation of the two models.
One obvious difference is that in the first model (fitagecovariate) one
can make infere...