POWER AND MONEY - DESIGNING STATISTICALLY POWERFUL STUDIES WHILE MINIMIZING FINANCIAL COSTS

Adequate statistical power is increasingly demanded in research design . However, obtaining adequate research funding is increasingly difficu lt. This places researchers in a difficult position. In response, the authors advocate an approach to designing studies that considers stati stical power and financial concerns simultaneously. Their purpose is t wofold: (a) to introduce the general paradigm of cost optimization in the context of power analysis and (b) to present techniques for such o ptimization. Techniques are presented in the context of a randomized c linical trial. The authors consider (a) selecting optimal cutpoints fo r subject screening tests; (b) optimally allocating subjects to differ ent treatment conditions; (c) choosing between obtaining more subjects or taking more replicate measurements; and (d) using prerandomization covariates.