Hi,
when I generated a survfit() object, I can get number
of patients at risk at various time points by using
summary():
fit<-survfit(Surv(time,status)~class,data=mtdata)
summary(fit)
class=1
time n.risk n.event survival std.err lower 95% CI
upper 95% CI
9.9 78 1 0.987 0.0127 0.963 1
41.5 77 1 0.974 0.0179 0.940 1
54.0 76 1 0.962 0.0218 0.920 1
99.1 38 1 0.936 0.0328 0.874 1
class=2
time n.risk n.event survival std.err lower 95% CI
upper 95% CI
6.9 102 1 0.990 0.00976 0.971 1.000
8.0 101 1 0.980 0.01373 0.954 1.000
14.4 100 1 0.971 0.01673 0.938 1.000
16.1 99 1 0.961 0.01922 0.924 0.999
16.6 98 1 0.951 0.02138 0.910 0.994
18.7 97 1 0.941 0.02330 0.897 0.988
:
:
:
I have many censoring observations in the dataset, and
I would like to know the number of patients at risk
(n.risk in the above output) for certain time points,
for example at 60, 72, etc, which is not available
from the above printout for class=1. Is there anyway I
can get them?
Thanks
array chip wrote:> Hi, > > when I generated a survfit() object, I can get number > of patients at risk at various time points by using > summary(): > > fit<-survfit(Surv(time,status)~class,data=mtdata) > summary(fit) > > class=1 > time n.risk n.event survival std.err lower 95% CI > upper 95% CI > 9.9 78 1 0.987 0.0127 0.963 1 > 41.5 77 1 0.974 0.0179 0.940 1 > 54.0 76 1 0.962 0.0218 0.920 1 > 99.1 38 1 0.936 0.0328 0.874 1 > > class=2 > time n.risk n.event survival std.err lower 95% CI > upper 95% CI > 6.9 102 1 0.990 0.00976 0.971 1.000 > 8.0 101 1 0.980 0.01373 0.954 1.000 > 14.4 100 1 0.971 0.01673 0.938 1.000 > 16.1 99 1 0.961 0.01922 0.924 0.999 > 16.6 98 1 0.951 0.02138 0.910 0.994 > 18.7 97 1 0.941 0.02330 0.897 0.988 > : > : > : > > I have many censoring observations in the dataset, and > I would like to know the number of patients at risk > (n.risk in the above output) for certain time points, > for example at 60, 72, etc, which is not available > from the above printout for class=1. Is there anyway I > can get them? > > ThanksThe Design package's survplot function can print n.risk over equally spaced time points. You might see an easy way to print this by looking at the code. -Frank -- Frank E Harrell Jr Professor and Chair School of Medicine Department of Biostatistics Vanderbilt University
Have you looked at the times argument to the summary method? --Matt Matt Austin Statistician Amgen One Amgen Center Drive M/S 24-2-C Thousand Oaks CA 93021 (805) 447 - 7431> -----Original Message----- > From: r-help-bounces at stat.math.ethz.ch > [mailto:r-help-bounces at stat.math.ethz.ch]On Behalf Of array chip > Sent: Friday, February 04, 2005 12:2 PM > To: r-help at stat.math.ethz.ch > Subject: [R] no. at risk in survfit() > > > Hi, > > when I generated a survfit() object, I can get number > of patients at risk at various time points by using > summary(): > > fit<-survfit(Surv(time,status)~class,data=mtdata) > summary(fit) > > class=1 > time n.risk n.event survival std.err lower 95% CI > upper 95% CI > 9.9 78 1 0.987 0.0127 0.963 1 > 41.5 77 1 0.974 0.0179 0.940 1 > 54.0 76 1 0.962 0.0218 0.920 1 > 99.1 38 1 0.936 0.0328 0.874 1 > > class=2 > time n.risk n.event survival std.err lower 95% CI > upper 95% CI > 6.9 102 1 0.990 0.00976 0.971 1.000 > 8.0 101 1 0.980 0.01373 0.954 1.000 > 14.4 100 1 0.971 0.01673 0.938 1.000 > 16.1 99 1 0.961 0.01922 0.924 0.999 > 16.6 98 1 0.951 0.02138 0.910 0.994 > 18.7 97 1 0.941 0.02330 0.897 0.988 > : > : > : > > I have many censoring observations in the dataset, and > I would like to know the number of patients at risk > (n.risk in the above output) for certain time points, > for example at 60, 72, etc, which is not available > from the above printout for class=1. Is there anyway I > can get them? > > Thanks > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! > http://www.R-project.org/posting-guide.html >