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Estimating survival?

4 messages · Min-Han Tan, Frank E Harrell Jr, Thomas Lumley

Original
Min-Han Tan
# 
Hi,

Sorry to trouble the list. I have a problem which I'm not sure how to resolve.

I have a Cox model with 1 independent variable with 2 categories (and
thus 2 survival curves on plotting survfit)

How can I get an estimate of survival for each category at a
particular time point, with standard error?
 
Looking through ?cph and ?coxph, I'm not quite sure how to go about
that. I would really appreciate any direction here.

Thanks a million!

Min-Han
Min-Han Tan
# 
Apologies, I located the function in cph (... time.inc =30, surv = TRUE)
...
$surv.summary


Thanks.
Min-Han
On Tue, 2 Nov 2004 21:06:33 -0500, Min-Han Tan <minhan.science at gmail.com> wrote:
Frank E Harrell Jr
#
Min-Han Tan wrote:
The survest function in the Design package makes this easy.  You can 
also probably do it without a lot of hassle using standard survival 
package routines. With survest you can easily specify covariate 
combinations for which to obtain predictions.
Thomas Lumley
#
On Tue, 2 Nov 2004, Min-Han Tan wrote:

            

      
      
      
    

        
Here's an example

            

      
      
      
    

        
Call: survfit.coxph(object = fit, newdata = list(rx = c(1, 2)))

  time n.risk n.event survival1 survival2
    59     26       1     0.952     0.973
   115     25       1     0.903     0.945
   156     24       1     0.855     0.917
   268     23       1     0.806     0.888
   329     22       1     0.758     0.858
   353     21       1     0.710     0.828
   365     20       1     0.663     0.797
   431     17       1     0.613     0.764
   464     15       1     0.560     0.727
   475     14       1     0.509     0.689
   563     12       1     0.454     0.648
   638     11       1     0.403     0.606


 	-thomas