From the Department of Comparative Biomedical Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom.
Department of Epidemiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
Epidemiology. 2024 Nov 1;35(6):801-804. doi: 10.1097/EDE.0000000000001770. Epub 2024 Jul 23.
The relevance of the epidemiologic concept of preventable fraction to the study of the population-level impact of preventive exposures is unequivocal. Here, we discuss how the preventable fraction can be usefully understood for the class of outcomes that relate to disease progression (e.g., clinical severity given diagnosis), and, under the principal stratification framework, derive an expression for this quantity for this type of outcome. In particular, we show that, in the context of disease progression, the preventable fraction is a function of the effect on the postdiagnosis outcome in the principal stratum in the unexposed group who would have disease regardless of exposure status. This work will facilitate an understanding of the contribution of principal effects to the impact of preventive exposures at the population level.
流行病学中可预防部分的概念对于研究预防性暴露对人群水平的影响具有明确的相关性。在这里，我们讨论了如何在与疾病进展相关的结局类别（例如，给定诊断的临床严重程度）中，以及在主要分层框架下，对这种类型的结局有用地理解可预防部分。特别是，我们表明，在疾病进展的情况下，可预防部分是暴露组中主要分层中无论暴露状态如何都会患病的人群中，未暴露人群的发病后结局的影响的函数。这项工作将有助于理解主要效应在预防暴露对人群水平的影响中的贡献。
