Methods of sample size and power calculations are reviewed for the most common study
designs. The sample size and power equations for these designs are shown to be special
cases of two generic formulae for sample size and power calculations. A computer program
is available that can be used for studies with dichotomous, continuous, or survival response
measures. The alternative hypotheses of interest may be specified either in terms of differing
response rates, means, or survival times, or in terms of relative risks or odds ratios. Studies …