Hello,
Can someone tell me why I am getting the following warning?
proc power;
twosamplesurvival
curve("23")= (119 127 197 1115 1321 1391) : (0.938 0.875 0.813 0.75 0.688 0.625)
curve("411")= (56) : (0.928)
groupsurvival="23"|"411"
totaltime=4185
test=logrank
accrualtime=1
alpha=0.05
npergroup=16 14
power=.;
run ;
WARNING: The magnitude of the effect is ill-defined in 2 scenarios in the output table.
My goal is to compare 2 survival curves, one with 6 deaths (n = 16 total) and one with 1 death (n = 14 total), the total time is 4185 minutes.
SAS does do the analysis but this is my output:
Computed Power Index N per Group Power Error 1 2
| 16 | . | Invalid input |
| 14 | . | Invalid input |
I am using SAS University edition.
Thank you in advance!
Andrea
