传染病病例对照研究中对照组筛检问题

A discussion on the screen of controls in case-control study of infec- tious diseases

作者报道不同人群免疫水平,普通人群与免疫人群不同暴露率,对优势比影响的模拟分析和一次流行性出血热病例对照研究中易感人群对照和普通人群对照的对比分析结果.发现当易感人群对研究因素的暴露率与普通人群接近时,两种对照的结果也很接近.当上述两种人群暴露率有明显差别时,则两种对照所得优势比也有明显差别,但分别与其相应目标人群的相对危险度接近.据此作者认为,传染病病例对照研究中对照组是否需要血清学筛检取决于:①筛检效益;②研究的目的及暴露与易感性是否有联系.如果两者无明显联系,或者欲得普通人群优势比,以普通人群对照为宜.若欲估计易感人群的优势比,则应选择易感人群对照.

A simulation analysis and a comparison analysis of susceptible population controls and general population controls in a case-control study of epidemic hemorrhagjc fever were reported. It was shown that, when the exposure rates for studying factors of susceptibles and that of general population were near-by, the results of both kinds of the controls were also near-by. When there was an obvious difference of exposure rates between both the controls, the difference of ORs of the two kinds of the controls might be obvious, but the odds were near-by estimates of RR of the corresponding target population. According to these results, the authors are of the opinion that whether the serological screen is needed during the selection of control in case-control study of infectious diseases is determined by the efficacy of serological screen and the research. Aim and the association of exposure and susceptibility. If there is no significant association between exposure and susceptibility, or the estimates of OR of general population is desirable, the general population control is preferable. When the estimates of OR of susceptible population is wanted, the susceptible population control should be selected.