Combined evidence from multiple outcomes in a clinical trial.

Clinical investigators are encouraged to apply recently developed statistical methodology. For each patient in a trial, favorable and unfavorable results from multiple outcomes may be summarized in a suitable summary measure. This summary measure may be used in a two-sample t-test to decide which treatment is best. An example illustrates how the evidence from the main outcome criteria may be combined. The required study size depends on the mean treatment effect on the outcomes in the summary measure. When separate outcomes are considered, there is a multiple comparisons problem, for which Hochberg offered a simple solution. Evaluation of a single-summary measure may require a larger or a smaller study size than evaluation of separate outcomes, depending on whether treatment effects are about the same or very different.