03-21-2017 05:26 AM
I am trying to analyse the survival rate of my subjects (pigs within a litter) during a trial (hereby the dataset). Everything seems to work fine apart from my summary statistics tables, which are empty for each of the strata....
I have a lot of censored data (very few subjects died, about 20%) and most of then are at the beginning of the trial, would it be a reason why my tables are empty ?
Here is my code :
PROC LIFETEST data = SURVIVAL_lect atrisk plots=survival(atrisk cl) outtest=outsurvival ;
STRATA treat / test=(logrank wilcoxon) adjust=Tukey;
test weight size PI BMI B_NCC B_U;
title 'effect of treatment on mortality - Kaplan-Meier' ;
Also, I have subjects that were removed from their original litter ("transferred") in the course of lactation, thus I have censored those ones as well, hoping it will help but there is no difference...
Thanks so much already !