Improved Confidence Intervals for the Difference between Two Proportions

Wald-z asymptotic methods, with and without a continuity correction, have less than nominal coverage probability characteristics but continue to be used. Newcombe\u27s hybrid method and the Agresti-Caffo methods have coverage probabilities that are near nominal for either equal or unequal samples. Newcombe\u27s hybrid and Agresti-Caffo methods demonstrate superior coverage properties