A prospective study on effect of periodic health examination for prevention of chronic diseases

组织了两组社区人口和一组工作人口，以评估定期健康检查对慢性病一级和二级预防的有效性。社区队列的成员是从1989年和/或1990年参加老年人保健方案提供的定期健康检查并提交书面协议成为队列成员的人中挑选出来的。一个州各市的工人组成了工人队伍。118个市共有22 478名工人在同一方案下接受定期健康检查。本文从健康教育和项目管理的角度分析了该检查的各项检查对疾病早期发现的有效性和检查的有效性。对于第一个分析，在对社区队列进行检查后，对平均117天的发病率进行了调查，结果显示47%的成员在此期间至少访问过一次医疗设施。只有15%的人被检查出。在此基础上，建立了一个数学模型，以估计当筛查测试应用于给定人群时亚临床疾病的可检测比例。模型引入的变量是检查的间隔时间、亚临床期的长度、特异性和敏感性。对职业队列的阳性预测值进行了估计。估计值的范围在20% ~ 96%之间分布很广。对6920名无糖尿病病史的工人进行糖尿病详细调查，发现空腹血糖379例阳性。在这个阳性组中，只有126人在检查后的一年内去看医生。检查后对社区队列的问卷调查证明，与检查前相比，生活方式有了实质性的改善。

Two cohorts of a community population and a working poplation have been organized to evaluate effectiveness of periodic health examination for primary and secondary prevention of chronic diseases. The member of the community cohort was selected from those who attended periodic health examinations offered by the Health Care Program for Senior Person in 1989 and/or 1990 and submitted written agreement to become a member of the cohort. Workers of municipalities in a prefecture composed the worker's cohort. A total of 22, 478 workers who belong one of 118 municipalities are offered periodic health examination under a same program. Analysis is done to clarify 1)effectiveness of each test of the examination for early detection of disease and 2)effectiveness of the examination from aspect of health education and program management. For the first analysis, a survey of incidence for average of 117 days after an examination of the community cohort revealed 47% of the member visited medical facilities at least once during the period. Only 15% of them were detected by the examination. Based on the results, a mathematical model was created to estimate detectable proportion of a subclinical disease when a screening test is applied to a given population. Introduced variables for the model are interval of the examination, length of subclinical stage, specificity and sensitivity of the test. Positive predictive values of the tests are estimated for the occupational cohort. The range of estimated values distributed rather widely from 20% to 96'/. . A detailed survey on diabetes mellitus revealed 379 positive cases on fasting blood sugar test among 6920 workers who have no history of diabetes. Amonly this positive group only 126 visited physicians during one year after the examination. A postexamination questionnaire survey of the community cohort proved a substantial improvement in life style if it is compared to the preexamination.