help drawing kaplan-meier plot starting from 0
On Thu, 16 Jan 2003, Frank Mattes wrote:
Dear help news reader, I'm trying to draw a Kaplan-Meier curve and would like to ask the news group for some help Supposing I have study comapring two drugs, "A", and "B" and I recorde the time to get to the clinical endpoint (Time), in my case becommming virus free.
<various stufff>
which gives me a Kaplan-Meier Curve, starting with 1. However I would like to the a plot starting with "0" and than showing the increasing numbers of patients becomming "virus negative".
You want the fun="event" option to plot.survfit. Eg
data(aml)
leukemia.surv <- survfit(Surv(time, status) ~ x, data = aml)
# usual plot
plot(leukemia.surv, lty = 2:3)
# cdf (event) ploot
plot(leukemia.surv, lty = 2:3,fun="event")
-thomas
Thomas Lumley Asst. Professor, Biostatistics
tlumley at u.washington.edu University of Washington, Seattle