Pennington Biomedical Research Center, Baton Rouge, LA 70808, United States.
Contemp Clin Trials. 2013 Jan;34(1):10-20. doi: 10.1016/j.cct.2012.08.011. Epub 2012 Sep 5.
The Comprehensive Assessment of the Long-term Effects of Reducing Intake of Energy Phase 2 (CALERIE) study is a systematic investigation of sustained 25% calorie restriction (CR) in non-obese humans. CALERIE is a multicenter (3 clinical sites, one coordinating center), parallel group, randomized controlled trial. Participants were recruited, screened, and randomized to the CR or control group with a 2:1 allocation. Inclusion criteria included ages 21-50 years for men and 21-47 years for women, and a body mass index (BMI) of 22.0 ≤ BMI < 28.0 kg/m(2). Exclusion criteria included abnormal laboratory markers, significant medical conditions, psychiatric/behavioral problems, and an inability to adhere to the rigors of the evaluation/intervention schedule. A multi-stage screening process (telephone screen and 3 in-clinic visits) was applied to identify eligible participants. Recruitment was effective and enrollment targets were met on time. 10,856 individuals contacted the clinical sites, of whom 9787 (90%) failed one or more eligibility criteria. Of the 1069 volunteers who started the in-clinic screening, 831 (78%) were either ineligible or dropped. 238 volunteers were enrolled (i.e., initiated the baseline evaluations), 220 were randomized, and 218 started the assigned intervention (2% from the first screening step). This study offered lessons for future multi-center trials engaging non-disease populations. Recruitment strategies must be tailored to specific sites. A multi-disciplinary screening process should be applied to address medical, physical, and psychological/behavioral suitability of participants. Finally, a multi-step screening process with simple criteria first, followed by more elaborate procedures has the potential to reduce the use of study resources.
CALERIE 研究（减少能量摄入的长期影响综合评估 2 期）是对非肥胖人群进行持续 25%热量限制（CR）的系统研究。CALERIE 是一项多中心（3 个临床站点，一个协调中心）、平行组、随机对照试验。参与者通过 2:1 的分配被招募、筛选并随机分配到 CR 或对照组。纳入标准包括男性年龄 21-50 岁，女性年龄 21-47 岁，体重指数（BMI）为 22.0≤BMI＜28.0kg/m(2)。排除标准包括实验室指标异常、严重疾病、精神/行为问题以及无法遵守评估/干预计划的严格要求。采用多阶段筛选过程（电话筛选和 3 次门诊访视）来确定合格的参与者。招募工作有效，按时达到了入组目标。10856 人联系了临床站点，其中 9787 人（90%）因一项或多项资格标准而不合格。在开始门诊筛查的 1069 名志愿者中，831 人（78%）不合格或退出。238 名志愿者入组（即开始基线评估），220 人被随机分组，218 人开始接受指定的干预（从第一步筛选开始的 2%）。这项研究为未来涉及非疾病人群的多中心试验提供了经验教训。招募策略必须针对特定的地点进行调整。应采用多学科筛选程序，以解决参与者的医学、身体和心理/行为适应性问题。最后，采用简单标准的多步骤筛选过程，然后再进行更详细的程序，有可能减少研究资源的使用。
