Slide 6 of 16

4. We were guided by findings from the CARDIA study in setting our severity thresholds for aortic and mitral regurgitation. In CARDIA, 4532 randomly selected, asymptomatic subjects age 23-35 underwent 2-D and doppler echocardiography. While regurgitation of a minimal degree was fairly common, aortic regurgitation of mild or greater severity was found in only 1.2%. Mitral regurgitation of moderate or greater severity was found in 1.0%. By setting our "research" case definition at these thresholds, we hoped to minimize the misclassification of "normal" background regurgitation with that potentially attributable to appetite suppressant use.