Morrison T C, Wahlgren D R, Hovell M F, Zakarian J, Burkham-Kreitner S, Hofstetter C R, Slymen D J, Keating K, Russos S, Jones J A
Center For Behavioral Epidemiology and Community Health, Graduate School of Public Health, San Diego State University 92182-0405, USA.
Control Clin Trials. 1997 Oct;18(5):383-96. doi: 10.1016/s0197-2456(97)00025-1.
This paper reports a multi-dimensional approach to minimize drop-outs from a two-year follow-up of a clinical trial designed to reduce initiation of tobacco use in 16,915 adolescent orthodontic patients. A hierarchical approach to data collection and tracking was employed. Seventy percent of participants were reached and interviewed at home by telephone. Strategies used to survey remaining participants included calling parents' work numbers and directory assistance, reviewing orthodontists' charts, sending surveys by mail, offering incentives, and using reverse telephone directories. More than 92% of the participants completed follow-up surveys. Multivariate analyses showed that baseline tobacco and alcohol use predicted loss to follow-up. Similarly, the number of procedures used to track each participant predicted presence of risk behaviors at post-test, demonstrating that an organized tracking hierarchy curtailed even greater compromises to internal and external validity. Evaluation and costs of individual strategies are discussed.
本文报告了一种多维方法，用于尽量减少一项旨在减少16915名青少年正畸患者开始吸烟的临床试验两年随访中的失访情况。采用了分层的数据收集和跟踪方法。70%的参与者通过电话在家中接受了联系和访谈。用于调查其余参与者的策略包括拨打家长的工作电话和查号台、查阅正畸医生的图表、邮寄调查问卷、提供激励措施以及使用反向电话簿。超过92%的参与者完成了随访调查。多变量分析表明，基线时的吸烟和饮酒情况可预测失访情况。同样，用于跟踪每位参与者的程序数量可预测测试后风险行为的存在情况，这表明有组织的跟踪层级减少了对内部和外部有效性的更大损害。文中讨论了各个策略的评估和成本。
