The formula for a chi-square test is equal to the sum of the observed minus the expected squared, divided by the .
USMLE® Step 1 style questions USMLE
A 24-month randomized clinical trial is being conducted at a high volume otolaryngology clinic to study a new surgical augmentation agent in sinus surgery for bilateral nasal polyposis (nasal polyps). The study is comparing the outcomes of the standard of therapy (surgical removal) with the addition of a temporary implantable agent laced with betamethasone (corticosteroid). The patients are randomized to each group and post-operative outcomes are collected including morphine equivalents for pain, presence or absence of anosmia, bleeding, and regrowth of polyps. The data are collected in 246 patients. Which of the following is the most appropriate statistical test to compare the two groups regarding anosmia?