Simulation results for a binary endpoint based on 2000 Monte Carlo data sets of size 1000. For IPW, a logistic regression for the propensity score includes all 20 X variables is fitted to the data. For ANCOVA, all 20 X variables are included in the model. For OPT, all 20 X variables are included in separate logistic outcome regression models for the two arms. SEM is the standard error based on Monte Carlo samples; SEA is the average of large sample standard error estimates over the Monte Carlo samples. Cov.Prob. is the coverage probability of the 95% confidence interval based on large-sample normal approximation. (Δ0,Δ1) are the true proportions in the control and intervention arms, respectively.