This book explains how the formulas and procedures for sample size calculations can be used in a variety of clinical research and development stages. It presents real-world examples from several therapeutic areas and explores emerging topics in pharmaceutical research and development. This edition now provides sample size calculations for dose response studies, microarray studies, and Bayesian approaches. It also includes a basic version of PharmaSoftware Solutions, Inc.’s N Solution 2007. Along with sensitivity analyses for each procedure, the software contains all procedures for testing equality, superiority/noninferiority, and equivalence for comparing means, proportions, and time-to-event data.