Sample size graphs for "proving the null hypothesis"

Control Clin Trials. 1984 Jun;5(2):97-105. doi: 10.1016/0197-2456(84)90116-8.


Sample size graphs are given for clinical trials designed to test whether an experimental therapy is as effective as a standard therapy. We assume a dichotomous outcome variable and a one-sided test of the hypothesis that the probability of success with standard therapy is greater than the probability of success with experimental therapy by at least some specified amount delta. Graphs are given for significance level alpha = 0.01, 0.025, 0.05; type II error beta = 0.10, 0.20; and delta = 0.10, 0.20.

MeSH terms

  • Clinical Trials as Topic / methods*
  • Humans
  • Probability
  • Research Design
  • Sampling Studies
  • Statistics as Topic*