--- begin included message -- I have some data which is censored and I want to determine the median. Its actually cost data for a cohort of patients, many of whom are still on treatment and so are censored.
I can do the same sort of analysis for a survival curve and get the median survival... ...but can I just use the survival curve functions to plot an X axis that is $ rather than date? If not is there some other way to achieve this? -- end inclusion -- 1. The survfit routines will work, and the results that you plot will indeed be on the dollar scale, BUT 2. The answer will be wrong. The reason is that the censoring occurs on a time scale, not a $ scale: you don't stop observing someone because total cost hits a threshold, but because calendar time does. The KM routines assume that the censoring process and the event process are on the same scale. The result can be an overestimation of cost. See Dan-Yu Lin, Biometrics 1997, "Estimating medical costs from incomplete follow-up data". Terry Therneau ______________________________________________ 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.
