Extending Power and Sample Size Approaches Developed for McNemar's Procedure to General Sign Tests

Summary Current software and textbooks present procedures to estimate power and sample size for sign tests that only apply to settings where positive (i.e., X = 1) or negative (i.e., X =−1), but not neutral (i.e., X = 0) outcomes occur. However, many studies analyzed by sign tests involve the more general setting where significant amounts of neutral outcomes can occur. This paper illustrates extension of existing power/sample size approaches and software that have been developed for matched binary responses (McNemar's discordant pairs) to general sign tests with neutral outcomes occurring. An application is made to a recent study that the author collaborated on.