Pharmaceutical Statistics Using SAS

10.1. Introduction

In their "Perspectives on Large-Scale Cardiovascular Clinical Trials for the New Millennium," Dr. Eric Topol and colleagues (1997) provide a fine preamble to our discussions:

The calculation and justification of sample size is at the crux of the design of a trial. Ideally, clinical trials should have adequate power, ≈90%, to detect a clinically relevant difference between the experimental and control therapies. Unfortunately, the power of clinical trials is frequently influenced by budgetary concerns as well as pure biostatistical principles. Yet an underpowered trial is, by definition, unlikely to demonstrate a difference between the interventions assessed and may ultimately be considered of little or no clinical value. From ...