Warmer Surgical Patients Recover Better? An article published in USA Today stated that “in a study of 200 colorectal surgery patients, 104 were kept warm with blankets and intravenous fluids; 96 were kept cool. The results show: Only 6 of those warmed developed wound infections vs. 18 who were kept cool.”

a. Use a 0.05 significance level to test the claim of the article’s headline: “Warmer surgical patients recover better.” If these results are verified, should surgical patients be routinely warmed?

b. If a confidence interval is to be used for testing the claim in part (a), what confidence level should be used?

c. Using the confidence level from part (b), construct a confidence interval estimate of the difference between the two population proportions.

d. In general, if a confidence interval estimate of the difference between two population proportions is used to test some claim about the proportions, will the conclusion based on the confidence interval always be the same as the conclusion from a standard hypothesis test?