Unequal Randomization Allocation and Cox Regression: A Simulation Study
نویسنده
چکیده
In terms of type I error rate, Log rank test and Wald test give similar results. We can see that when the randomization ratio is 1:1 for an event size of 600, no inflation of types I error rate is observed. However when the randomization ratio is 1:2 for an event size of 600, the type I error rate is inflated to about 0.027. The inflation becomes smaller when the sample size increases. However the inflation is not observable only when the sample size is impractically big. When the randomization is further imbalanced to 1:3 for sample size of 600, the type I error is further inflated to about 0.028. Introduction
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