“…A sample size of 154 subjects in the intent‐to‐treat (ITT) population, randomized in a 1 : 1 ratio into two treatment groups, was calculated to provide at least 80% power to detect a 0.75 dose reduction (>20% reduction in rescue analgesia) in the mean number of doses of postoperative fentanyl between patients receiving IV‐ibuprofen and those receiving placebo using a two‐sided Wilcoxon rank‐sum test assuming the mean number of doses in the placebo group is 3.5 at the significance level α = 0.05 and a standard deviation of 1.6 [based on reference and Moss JR, Cofer S, Hersey S, Goudy S, Werkhaven J, Swanson E, Mantle C, Stowell N, Byrne D, Wang L, Labadie R, unpublished data].…”