Abstract

SAS/STAT® 14.1 released in SAS® 9.4 TS1M3 can perform non-parametric method to calculate cumulative incidence function (CIF) and can create CIF plots by using PROC LIFETEST, but it can’t directly show the information such as number at risk. And in PROC PHREG, both Fine and Gray’s sub-distribution hazard model and cause-specific model are fitted when there is competing risk events. Up to date, there is no build-in variable selection procedure for the two kinds of models in SAS®. To address this limitation, we developed SAS® macros to apply Fine and Gray’s approach and cause-specific method with backwards elimination. The two macros generate summary reports in the form of tables displaying results that include, Hazard Ratio in the case of cox regression with its 95% confidence intervals, sample size, and p-values. We also created the third SAS macro to show CIF plot. Comparing with the CIF plot generated by default SAS® procedure, our SAS® CIF Plot macro provides more information including Gray’s test for the significant differences among the levels of a categorical covariate, a table with number at risk, accumulated number of events of interest, accumulated -events of competing for specified time-points at the bottom of the graph. And censored information also is shown in the CIF curve. The three macros used for competing risk survival data enable us to generate journal-quality summary tables and graphs, production of comprehension.

Keywords: Competing Risk, CIF, Number at Risk, Backward Elimination, Fine and Gray’s Model, Cause- Specific Hazard Model