The following data were collected in a clinical trial to compare a new drug to a placebo for its effectiveness in lowering total serum cholesterol. Generate a 95% confidence interval for the difference in mean total cholesterol levels between treatments.
New Drug (n=75) Placebo
(n=75) Total Sample
(n=150)
Mean (SD) Total Serum Cholesterol
185.0 (24.5)
204.3 (21.8)
194.7 (23.2)