自20世纪50年代以来,传统的病例-对照研究广泛应用于医学各个领域,以分析慢性疾病相关的危险因素的研究居多。然而传统病例-对照研究的难点在于选择合适的对照组。因此,相关学者就如何选择对照,提出并逐渐形成了非传统病例-对照研究方法,其中病例交叉研究(case-crossover study)是非传统病例-对照研究的一种。病例交叉研究特别适于研究罕见急性事件的危险因素,如心肌梗塞、伤害、支气管哮喘等。病例交叉研究以病例自身 Since the 1950s, traditional case-control studies have been widely used in various fields of medicine to analyze the risk factors associated with chronic diseases. However, the difficulty of the traditional case-control study lies in selecting the appropriate control group. Therefore, the relevant scholars on how to choose control, put forward and gradually formed a non-traditional case-control study, including case-crossover study (case-crossover study) is a non-traditional case-control study. Case-crossover studies are particularly well suited for studying risk factors for rare acute events such as myocardial infarction, injury, bronchial asthma, and the like. Case studies cross the case itself