Statistical Analysis
pain
An a priori power analysis was conducted to determine the number of patients needed to detect a difference in STAI scores between the groups. To detect a clinically meaningful difference of a change of 5 points in the STAI with a power of 0.8, a significance level of 0.05, and an SD of 8.9, 51 patients were needed in each group. The SD used was based on a separate study involving patients undergoing procedures under general anesthesia.To determine whether we were appropriately powered to detect a clinically meaningful difference of 2 points in VAS, we conducted a post-hoc power analysis: with 80% power to detect α = .05, based on our VAS SD of 3.12, we required 40 patients in each group; as there were only 24 patients who completed the pain portion of the postoperative survey, we did not reach appropriate confidence for definitive conclusion for this comparison.Continuous variables are presented as mean and SD. Categorical variables are presented as count and percentage. Mann-Whitney 