Pain after surgery: In a random sample of 57 patients undergoing a standard surgical procedure, 19 required medication for postoperative pain. In a random sample of 82 patients undergoing a new procedure, only 18 required pain medication (a) Construct a 90% confidence interval for the difference in the proportions of patients needing pain medication between the old and new procedures. Let P, denote the proportion of patients who had the old procedure needing pain medication and let p, denote the proportion of patients who had the new procedure needing pain medication. Use the T1-84 Plus calculator and round the answers to three decimal places A 90% confidence interval for the difference in the proportions of patients needing pain medication between the old and X new procedures is ___ < P1-p2 < ___
(b) a physician claim that the proportion of patients who need pain medication is the same for both procedures. does the confidence interval contradict the claim? because the confidence interval ____ 0, it ____ the claim that the proportion of patients who need pain medication is the same for both procedures.