Joint One-Sided and Two-Sided Simultaneous Confidence Intervals

Abstract

For the analysis of multiarmed clinical trials often a set consisting of a mixture of one- and two-sided tests can be preferred over a set of common two-sided hypotheses settings. Here we show the straightforward application of existing multiple comparison procedures for the difference and ratio of normally distributed means to complex trial designs, involving one and two test directions. The proposed contrast tests provide a more flexible framework than the existing methods at nearly similar power. An application is illustrated for an example with multiple treatment doses and two active controls; statistical software codes are included for R and SAS System.

Key Words:

• Clinical trials
• Multiple comparisons
• Simultaneous confidence intervals
• User-defined contrasts

ACKNOWLEDGMENTS

We thank Miriam Annett as well as two anonymous referees for several suggestions that have improved the presentation of this paper.