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Figure 9 Proposed three-stage approach for developing behavioral intervention trials. Stage 1 consists of a single-center evaluation of a specific behavioral intervention. If successful, this intervention would be repeated at multiple centers to assess the reproducibility of findings (stage 2). In both stages, intermediate end points, such as change in carotid intimal wall thickening or plaque size during carotid ultrasonography, would be used to minimize necessary sample size and follow-up time. If reproducible results are obtained during stage 2, a multicenter intervention trial would be performed in stage 3, during which subjects would be observed for the occurrence of hard cardiac events. IMT = intima medial thickness.
