Gareen Ilana F
Center for Statistical Sciences and the Department of Community Health, Brown University School of Medicine, Providence, RI 02912, USA.
Clin Trials. 2007;4(4):341-9. doi: 10.1177/1740774507081341.
Randomized trials evaluating new cancer screening technologies may underestimate the efficacy of screening to reduce cancer mortality if study participants are noncompliant. Participants may fail to comply with the screening itself or fail to obtain appropriate diagnostic follow-up and treatment. Noncompliance with screening has drawn wide attention, but little attention has been paid to noncompliance with diagnostic follow-up and treatment.
To examine the importance of noncompliance with screening, follow-up, and treatment in cancer screening trials.
The unique problems associated with noncompliance in screening trials are described and provide an example illustrating the potential impact of noncompliance in a screening trial. I discuss issues that arise with measurement of follow-up and therapeutic noncompliance, and the benefit of collecting information on health system and participant characteristics associated with noncompliance.
The estimate of the efficacy of a screening program on cancer mortality can be adjusted for screening, follow-up, and treatment noncompliance. Noncompliance needs to be measured in a rigorous, systematic manner across all arms of the trial. Information on health system and participant characteristics associated with compliance may also be incorporated into statistical models to estimate screening effects with full compliance, plan interventions to increase compliance, and extrapolate results of screening trials from one population to another.
Measuring compliance with follow-up and treatment can be difficult when these occur outside the trial, and when there is variation among providers in follow-up and treatment practices.
Noncompliance may alter the estimate of a screening effect on cancer mortality in clinical trials. It is possible to adjust screening efficacy estimates for noncompliance using existing statistical techniques. It is important that data describing compliance with screening, follow-up, and treatment are collected as part of standard data collection in cancer screening trials.
如果研究参与者不依从，评估新型癌症筛查技术的随机试验可能会低估筛查降低癌症死亡率的效果。参与者可能不依从筛查本身，或者未能获得适当的诊断后续检查及治疗。不依从筛查已引起广泛关注，但对诊断后续检查及治疗的不依从却很少受到关注。
探讨在癌症筛查试验中不依从筛查、后续检查及治疗的重要性。
描述了筛查试验中与不依从相关的独特问题，并提供了一个例子来说明不依从在筛查试验中的潜在影响。我讨论了在测量后续检查及治疗不依从时出现的问题，以及收集与不依从相关的卫生系统和参与者特征信息的益处。
可以针对筛查、后续检查及治疗不依从情况对筛查项目降低癌症死亡率的效果估计进行调整。需要在试验的所有组中以严格、系统的方式测量不依从情况。与依从性相关的卫生系统和参与者特征信息也可纳入统计模型，以估计完全依从时的筛查效果、规划提高依从性的干预措施，并将筛查试验结果从一个人群外推至另一个人群。
当后续检查及治疗在试验外进行，且提供者在后续检查及治疗实践中存在差异时，测量对其的依从性可能会很困难。
不依从可能会改变临床试验中筛查对癌症死亡率影响的估计。使用现有统计技术针对不依从情况调整筛查效果估计是可行的。作为癌症筛查试验标准数据收集的一部分，收集描述筛查、后续检查及治疗依从性的数据非常重要。
