Kopecky K and Green S (2012). Noninferiority trials. In: Handbook of Statistics in
Clinical Oncology. Crowley J and Hoering A, eds. CRC Press, Boca Raton, FL USA.
This program calculates the required sample size for a two-arm non-inferiority
design with a binomial outcome. N is calculated by the following formula for
specified power = 100(1- β)% and the true success probabilities are
PE and PS:
Alpha level (one-sided) α: The desired type I error rate. This
corresponds to a specification of a (1-2* α)% confidence interval around
the difference between the rates.
Power: Enter the desired power, 0-1, to rule out the null hypothesis
Noninferiority Margin: Enter the largest acceptable difference in
success rates between the standard arm and the experimental arm that would
be consistent with noninferiority.
Proportion of patients in the experimental arm (0.5): Enter the
proportion of patients (0-1) out of the total N that will be assigned to the
Success Probability in Standard Arm and Experimental Arm: Enter the
expected success probability for the standard arm, and the experimental arm.
Typically these are specified as equal, but equality is not required.