2.

Suppose a randomized study is done comparing cholesterol levels between subjects with a history of high cholesterol, randomized to receive either a drug, or a diet intervention. At the end of the study the average difference in cholesterol levels between the drug group compared to the diet group is 15 mg/dL, with a 95% CI (10 mg/dL, 20 mg/ dL). Suppose the results were re-presented with the direction of comparison being the difference for the diet group compared to the drug group. What would the resultin 95% CI for the mean difference be?

a. (10 mg/dL, 20 mg/dL)

b. (-10 mg/dL, 20 mg/dL)

c. (-20mg/dL, 10 mg/dL)

d. (-20mg/dL, -10 mg/dL)