A study done by the Ohio State University Medical Center examined whether or not taking an aspirin a day would help colon cancer patients reduce the chance of getting subsequent colon polyps. 635 patients with colon cancer participated; 317 of them were randomly assigned to the aspirin group, and the other 318 patients were assigned to a placebo (non-aspirin) group. 54 patients in the aspirin group developed subsequent polyps, compared to 86 patients in the non-aspirin group. In this study, all other outside factors (sex of the person, age, etc.) were controlled. A 95% confidence interval on the difference in proportions of the two groups [aspirin group (p1) minus non-aspirin group (p2)] was found to be -0.164 < p1 - p2 < -0.036. Which of the following interpretations of this confidence interval is most appropriate?
A.With 95% confidence, there is no statistically significant difference in the proportion of patients who developed polyps. Taking an aspirin a day is not effective in reducing the chance of developing subsequent polyps.
B.With 95% confidence, there is a statistically significant difference in the proportion of patients who developed polyps. Taking an aspirin a day appears to be effective in reducing the chance of developing subsequent polyps.
C.With 95% confidence we can say that taking an aspirin a day does not help.