Survival, Kaplan-Meier, left truncation
On Wed, Jan 07, 2004 at 12:57:46PM +0100, Rau, Roland wrote:
Dear all, I have data from 1970 to 1990 for people above age 50. Now I want to calculate survival curves by age starting at age 50 using the Kaplan Meier Estimator. The problem I have is that there are already people in 1970 who are older than 50 years. I guess this is called delayed entry or left truncation (?). I thought the code would be: roland <- survfit(Surv(time=age.enter, time2=age.exit, event=status, type="interval")~1, weights=gewicht, type="kaplan-meier")
Not type = "interval", but "count" (or just leave it out) You can also use 'plot.Surv' in package 'eha' (for plotting).
G?ran Brostr?m tel: +46 90 786 5223 Department of Statistics fax: +46 90 786 6614 Ume? University http://www.stat.umu.se/egna/gb/ SE-90187 Ume?, Sweden e-mail: gb at stat.umu.se