Omnibus Tests for Comparison of Competing Risks under the Additive Risk Model

Series
Stochastics Seminar
Time
Thursday, April 23, 2009 - 3:00pm for 1 hour (actually 50 minutes)
Location
Skiles 269
Speaker
Yichuan Zhao – Department of Mathematics, Georgia State University
Organizer
Heinrich Matzinger
It is of interest that researchers study competing risks in which subjects may fail from any one of k causes. Comparing any two competing risks with covariate effects is very important in medical studies. In this talk, we develop omnibus tests for comparing cause-specific hazard rates and cumulative incidence functions at specified covariate levels. The omnibus tests are derived under the additive risk model by a weighted difference of estimates of cumulative cause-specific hazard rates. Simultaneous confidence bands for the difference of two conditional cumulative incidence functions are also constructed. A simulation procedure is used to sample from the null distribution of the test process in which the graphical and numerical techniques are used to detect the significant difference in the risks. In addition, we conduct a simulation study, and the simulation result shows that the proposed procedure has a good finite sample performance. A melanoma data set in clinical trial is used for the purpose of illustration.