Zhang M, Zhu Y M, Li Y X, Mou Y T, Kan H, Fan W, Dai J H, Zheng Y J
Department of Epidemiology/Key Laboratory for Health Technology Assessment, National Commission of Health and Family Planning/Key Laboratory of Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai 200032, China.
Department of Epidemiology and Biostatistics, School of Public Health, Xinjiang Medical University, Urumqi 830011, China.
Zhonghua Liu Xing Bing Xue Za Zhi. 2021 Jul 10;42(7):1292-1298. doi: 10.3760/cma.j.cn112338-20200612-00839.
Epidemiological analysis describes and compares the characteristics of a certain number of people to make causal inferences. The formation of the study population is always the first step. In this paper, we first define the concepts of cross-sections at both individual level and population level and introduce the three assumptions needed in the measurements in observational studies, i. e. the true values of the attributes are stable with time, the attribute variables are independent and the individuals are independent during the measuring process. We also determine that the causal inference research should be unified based on the time of the occurrence or beginning of a postulated cause, or exposure, should be in. Then, based on the dual roles of the population cross-section with causal thinking, we propose that research designs can be classified into two types with different characteristics: history reconstruction research and future exploration research. Finally, we briefly analyze the research design framework and the relationship between estimated effects and different designs. The discussion of the formation of a study population from the perspective of causal thinking can make a foundation for the classification of causal inference research design with appropriate effect parameters, which needs to be further studied.
流行病学分析描述并比较一定数量人群的特征以进行因果推断。研究人群的形成始终是第一步。在本文中，我们首先定义个体层面和人群层面的横断面概念，并介绍观察性研究测量中所需的三个假设，即属性的真实值随时间稳定、属性变量相互独立且个体在测量过程中相互独立。我们还确定因果推断研究应基于假定原因或暴露发生或开始的时间进行统一。然后，基于人群横断面在因果思维中的双重作用，我们提出研究设计可分为具有不同特征的两类：历史重建研究和未来探索研究。最后，我们简要分析了研究设计框架以及估计效应与不同设计之间的关系。从因果思维角度对研究人群形成的讨论可为具有适当效应参数的因果推断研究设计分类奠定基础，这有待进一步研究。
