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Power Program

This program computes sample size or power for user specified null hypothesis and alternative hypothesis parameter values for a variety of experimental designs.
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Select one of the experimental designs:

  1. Comparative Clinical Trial with Loss to Follow-up and a Period of Continued Observation [ref: Rubinstein, Gail, & Santner]
  2. Long-term Medical Trial with Time-Dependent Dropout and Event Rates [ref: Wu, Fisher, & Demets]
  3. Clinical Trial with Strata-Specific Event Rates and Unequal Group Allocation [ref: Bernstein, Lagakos]
  4. Power Computations for Designing Comparative Poisson Trials with Unequal Group Sizes [ref: Brown & Green]
    1. Poisson Trials with Unequal Group Sizes, Adjusted for Compliance [ref: Brown & Green; Prorok]
  5. Unstratified Cohort Studies with a Dichotomous Disease Outcome [ref: Schlesselman]
  6. Case-Control Studies with a Dichotomous Exposure Outcome
    1. Unmatched Study with an Unequal Number of Cases and Controls [ref: Schlesselman]
    2. Frequency Matched Study with Equal Numbers of Cases and Controls and Strata Specific Exposures [ref: Gail]
    3. Matched Study with Multiple Controls per Case and Variable Exposures [ref: Miettinen]
  7. Anova Experiments with 3 or More Treatments[ref: Abramowitz & Stegun]
  8. Standard Statistical Problems Using Normal Approximations [ref: Lachin]
  9. Group Randomization [ref: Grizzle & Feng]
  10. Ordered Categorical Data [ref: Whitehead]
  11. Proving the Null Hypothesis [ref: Blackwelder]
  12. Mantel-Haenszel Test Simulation [ref: Mantel & Hankey]