arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1908.05955stat.ME
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复杂干预外部预试验的贝叶斯设计与分析

Bayesian design and analysis of external pilot trials for complex interventions

Duncan T. Wilson, James M. S. Wason, Julia Brown, Amanda J. Farrin, Rebecca E. A. Walwyn

摘要:

复杂干预措施的外部试点试验用于帮助确定是否以及如何进行确证性试验,提供招募率、保留率和依从率等参数的估计值。进入确证性试验的决定通常是通过将这些估计值与预先规定的阈值(称为进展标准)进行比较来做出的,尽管很少评估此类决定规则的统计学特性。这种评估因若干方法上的挑战而变得复杂,包括同时评价多个终点、复杂的多水平模型、小样本量以及干扰参数的不确定性。为了应对这些挑战,我们描述了贝叶斯方法的设计和分析的外部试点试验。我们展示了如何通过最小化损失函数的期望值来做出渐进决策,该损失函数定义在整个参数空间中,以允许在决策过程中表达和使用多个参数之间的偏好和权衡。通过使用损失函数的分段常数参数化来保持偏好的评估是可行的,损失函数的参数在设计阶段被选择以导致期望的操作特性。我们描述了一个灵活的,但计算密集,嵌套蒙特卡罗算法估计操作特性。该方法是用来重新设计的一个复杂的干预措施,旨在增加护理院居民的身体活动的外部试点试验。

英文摘要:

External pilot trials of complex interventions are used to help determine if and how a confirmatory trial should be undertaken, providing estimates of parameters such as recruitment, retention and adherence rates. The decision to progress to the confirmatory trial is typically made by comparing these estimates to pre-specified thresholds known as progression criteria, although the statistical properties of such decision rules are rarely assessed. Such assessment is complicated by several methodological challenges, including the simultaneous evaluation of multiple endpoints, complex multi-level models, small sample sizes, and uncertainty in nuisance parameters. In response to these challenges, we describe a Bayesian approach to the design and analysis of external pilot trials. We show how progression decisions can be made by minimising the expected value of a loss function, defined over the whole parameter space to allow for preferences and trade-offs between multiple parameters to be articulated and used in the decision making process. The assessment of preferences is kept feasible by using a piecewise constant parameterisation of the loss function, the parameters of which are chosen at the design stage to lead to desirable operating characteristics. We describe a flexible, yet computationally intensive, nested Monte Carlo algorithm for estimating operating characteristics. The method is used to revisit the design of an external pilot trial of a complex intervention designed to increase the physical activity of care home residents.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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