1 Division of Oral Epidemiology & Dental Public Health, University of California at San Francisco, CA, USA.
2 Department of Statistics, Wharton School, University of Pennsylvania, PA, USA.
Stat Methods Med Res. 2018 Sep;27(9):2756-2774. doi: 10.1177/0962280216686131. Epub 2017 Jan 8.
Different conventional and causal approaches have been proposed for mediation analysis to better understand the mechanism of a treatment. Count and zero-inflated count data occur in biomedicine, economics, and social sciences. This paper considers mediation analysis for count and zero-inflated count data under the potential outcome framework with nonlinear models. When there are post-treatment confounders which are independent of, or affected by, the treatment, we first define the direct, indirect, and total effects of our interest and then discuss various conditions under which the effects of interest can be identified. Proofs are provided for the sensitivity analysis proposed in the paper. Simulation studies show that the methods work well. We apply the methods to the Detroit Dental Health Project's Motivational Interviewing DVD trial for the direct and indirect effects of motivational interviewing on count and zero-inflated count dental caries outcomes.
不同的传统和因果方法已经被提出用于中介分析，以更好地理解治疗的机制。计数和零膨胀计数数据出现在生物医学、经济学和社会科学中。本文考虑了潜在结果框架下的计数和零膨胀计数数据的中介分析，其中包括非线性模型。当存在与治疗无关或受治疗影响的治疗后混杂因素时，我们首先定义我们感兴趣的直接、间接和总效应，然后讨论在哪些条件下可以识别出感兴趣的效应。本文提出的敏感性分析的证明。模拟研究表明，这些方法效果良好。我们将这些方法应用于底特律牙科健康项目的动机性访谈 DVD 试验，以评估动机性访谈对计数和零膨胀计数龋齿结果的直接和间接效应。
