Question in brief: can you/ how do you implement fitting alternate distributions in ICLIFETEST, and do I really need to? I ask, because I think the PROC fits an assumed distribution (normal I assume), and I read somewhere--probably for one of the other survival analysis PROCs--that you can specify a distribution to fit your data to. I have left censored data with variable censoring ranges, and none of the whole or the subsets of data I am analyzing can be transformed to provide normality. The data are mostly theoretically ~lognormal, are leptokurtotic, and highly skewed right, but no one transformation can be used on the data set as a whole, hence the nonparametric route. Also, I would like to run the procedure and get an lsmeans/ tukeyHSD type output for multiple comparisons, but have been thwarted since using a BY statement precludes that and has led me to separate analyses to compare years within treatment and treatment within year. I get an F test, but I have to go to PROC GLM (adjust=tukey) to get individual comparisons. And, unfortunately I have unbalanced samples and have to use LSMEANS in GLM, which doesn't allow for a Tukey HSD test. Any solutions that I am overlooking? Here's a piece of my script. It runs w/o errors. title "Survival Analysis Calcium Tiles Test Treatment by Year";
proc iclifetest data=Work.CaTiles method=EMICM plots=survival (failure) plots=logsurv
impute(seed=0);
STRATA Year;
test Treatment / Adjust=Tukey;
time (lower,upper);
run;
title "Survival Analysis Calcium Tiles Test Treatment All Years";
proc iclifetest data=Work.CaTiles method=EMICM plots=survival (failure) plots=logsurv
impute(seed=0);
test Treatment / Adjust=Tukey;
time (lower,upper);
run;
/*SUBSETTING: excludes 2007 data because no ST to compare*/
Data CaRunoffne2007;
set CaRunoff;
where Year ne 2007;
run;
PROC SORT DATA = CaRunoffne2007;
BY Year Treatment;
title "Survival Analysis Calcium Runoff Test Treatments by Year";
proc iclifetest data=Work.CaRunoffne2007 method=EMICM plots=survival (failure) impute(seed=0);
STRATA Year;
test Treatment / Adjust=Tukey;
time (lower,upper);
run;
PROC SORT DATA = CaRunoffne2007;
BY Treatment Year;
title "Survival Analysis Calcium Runoff Test Years by Treatment";
proc iclifetest data=Work.CaRunoffne2007 method=EMICM plots=survival (failure) impute(seed=0);
STRATA Treatment;
test Year / Adjust=Tukey;
time (lower,upper);
run;
title "Survival Analysis Calcium Runoff Test Treatments All Years";
proc iclifetest data=Work.CaRunoff method=EMICM plots=survival (failure) plots=logsurv
impute(seed=0);
test Treatment / Adjust=Tukey;
time (lower,upper);
run;
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