Hollis J F, Satterfield S, Smith F, Fouad M, Allender P S, Borhani N, Charleston J, Hirlinger M, King N, Schultz R
Kaiser Permanente Center for Health Research, Portland, OR 97227-1098, USA.
Ann Epidemiol. 1995 Mar;5(2):140-8. doi: 10.1016/1047-2797(94)00058-2.
Phase II of the Trials of Hypertension Prevention is a multicenter, randomized, controlled trial designed to determine the efficacy of weight loss and reduction of sodium intake for lowering blood pressure and incidence of hypertension among persons with high-normal levels of blood pressure. The 2 x 2 factorial study design includes weight loss alone, restricted sodium intake alone, the combination of weight loss and sodium restriction, and a control group. Nine clinical centers used a variety of recruitment strategies to enroll 2382 participants over 17 months, which exceeded the sample size goal of 2250. Among randomized participants, 21% were minorities and 34% were women. Overall, direct mail generated the most randomized participants (73%), followed by community screening (12%) and media advertisement (11%). Referrals from community health care providers yielded few participants. Prescreening improved overall efficiency and reduced costs. Participants who were more likely to drop out voluntarily during the three-visit screening regimen tended to be younger, single, male, smokers, and less educated.
高血压预防试验的第二阶段是一项多中心、随机、对照试验，旨在确定体重减轻和减少钠摄入量对血压处于正常高值的人群降低血压及高血压发病率的疗效。2×2析因研究设计包括单纯体重减轻、单纯限制钠摄入、体重减轻与钠限制相结合以及一个对照组。九个临床中心采用了多种招募策略，在17个月内招募了2382名参与者，超过了2250名的样本量目标。在随机分组的参与者中，21%为少数族裔，34%为女性。总体而言，直接邮寄招募的随机参与者最多（73%），其次是社区筛查（12%）和媒体广告（11%）。社区医疗服务提供者的推荐招募的参与者很少。预筛查提高了整体效率并降低了成本。在三次就诊筛查方案中更有可能自愿退出的参与者往往更年轻、单身、男性、吸烟者且受教育程度较低。
