The sample size required was based on: 1) postoperative retained endotracheal tube incidence of 0.413; 2) a Type I error of 0.05; 3) an absolute precision of 0.005; and, 4) an 80% power.
The sample size requiredwas based on: 1) postoperative retained endotracheal tubeincidence of 0.413; 2) a Type I error of 0.05; 3) an absoluteprecision of 0.005; and, 4) an 80% power.