Moore H, Summerbell C, Vail A, Greenwood D C, Adamson A J
Centre for Research in Primary Care, University of Leeds, Leeds, UK.
Stat Med. 2001 Feb 15;20(3):331-40. doi: 10.1002/1097-0258(20010215)20:3<331::aid-sim795>3.0.co;2-k.
The aim of this paper is to describe the design features and practicalities of conducting a cluster randomized trial of obesity management in primary care. The aim of the trial is to assess the effectiveness of an obesity management educational intervention delivered to staff within primary care practices (unit of randomization) in terms of change in body weight of their patients (unit of analysis) at one year. The design features which merit particular attention in this cluster randomized trial include standardization of intervention, sample size considerations, recruitment of patients prior to randomization of practices, method of randomization to balance control and intervention practices with respect to practice and patient level characteristics, and blinding of outcome assessment. The practical problems (and our solutions) associated with implementing these design features, particularly those that result in a time delay between baseline data collection, randomization and intervention, are discussed.
本文旨在描述在初级保健中进行肥胖管理整群随机试验的设计特点及实际情况。该试验的目的是评估在初级保健机构（随机分组单位）内向工作人员提供的肥胖管理教育干预措施，对其患者（分析单位）一年后的体重变化而言的有效性。在这项整群随机试验中，特别值得关注的设计特点包括干预措施的标准化、样本量的考量、在机构随机分组之前招募患者、使对照和干预机构在机构及患者层面特征方面达到平衡的随机分组方法，以及结果评估的盲法。本文还讨论了与实施这些设计特点相关的实际问题（以及我们的解决办法），尤其是那些导致基线数据收集、随机分组和干预之间出现时间延迟的问题。
