分层比例抽样
Methods Non-proportional stratified cluster sampling was used for this study. Oral examination was conducted according to diagnosis criteria for caries of WHO.
方法采用分层、不等比、多阶段整群抽样方法进行抽样,按照WHO龋病诊断标准进行口腔检查。
Methods With proportional stratified sampling and cluster sampling method, 3555 subjects were selected including officials, company staff, high school students, community population and floating population.
方法采用多阶段按比例随机抽样和整群抽样相结合的方法,抽取公务员、公司职员、高中生、社区居民、流动人口共计3555人,用国际体力活动量表长卷进行调查。
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