病例对照研究 (casecohortstudy)是选择所研究疾病的一组患者与一组无此病的对照 ,调查他们对某个 (些 )因素的暴露情况 ,比较两组中暴露率或暴露水平的差异 ,以研究疾病与这个 (些 )因素的关系 ,其要点包括 :1提出可疑危险因素 :临床医生根据临床观察、病例总结及阅读医学文献 A case-control study (case cohortstudy) is a group of patients selected for the disease in question and a group of controls without the disease, and their exposure to a factor(s) is investigated to compare the difference in exposure or exposure levels between the two groups. To study the relationship between disease and these (some) factors, the main points include: 1 Suspicious risk factors: clinicians based on clinical observation, case summary and reading medical literature