准实验中常用的统计分析方法及其在医学中的应用

Common statistical methods used in quasi-experimental studies and applications in medicine

受医学伦理或实际环境限制,随机对照试验的开展往往会受到限制。准实验研究通过控制研究的混杂效应,可在非随机化条件下进行因果推断,在某些情况下成为随机对照试验的替代选择。本文从准实验研究设计的基本思想、特点、局限性及在医学中的应用等角度,介绍准实验研究中常用的统计分析方法,包括双重差分模型、工具变量法、断点回归设计、间断时间序列模型等,以期为以后准实验研究提供参考。

Randomized controlled trials(RCTs)are often limited because of ethical or operational reasons.Quasiexperimental studies could be an alternative to RCTs to make causal inferences without randomization by controlling the confounding effects of the study.This paper introduced the general statistical analysis methods of quasi-experimental design through basic ideas,characteristics,limitations and applications in medicine,including difference-in-difference models,instrumental variables,regression discontinuity design,interrupted time series,and so on,and to provide references for future research.