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.

Description

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
P_{E} and P_{S}:

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
of inferiority.

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
experimental arm.

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.

Input Items (Success Probability input option)

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
of inferiority.

Success Probability in Experimental Arm (Under H0): Enter the assumed
success probability under the null hypothesis. Note that the difference between
the success probability in the standard arm, and this input, is the largest
acceptable difference 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
experimental arm.

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.