***********************************************************************
* This is a program that illustrates the use of PROC POWER to         *
* calculate sample size when comparing two binomial proportions in a  *
* non-inferiority trial.                                              *
***********************************************************************;

proc power;
twosamplefreq groupweights=(1 1) groupps=(0.65 0.70) alpha=0.025 power=0.9
   test=PChi sides=1 ntotal=.;
plot min=0.1 max=0.9;
title "Sample Size Calculation for Comparing Two Binomial Proportions (1:1 Allocation"
title2 "in a Non-Inferiority Trial"; 
run;