查询词典 stratified sample

Methods Stratified Cluster Sample was used in survey on middle-school students in Mengcheng County.

方法采用分层整群抽样方法对蒙城县中学生进行基线和干预后艾滋病相关问题的问卷调查。

Methods A cluster stratified sample of 1747 undergraduates were investigated b a self-designed questionnaire.

整群分层抽取郑州市1747名大学生为调查对象，自行设计问卷进行调查。

Methods A cluster stratified sample of 509 medical college students were questionnaired on epidemic features and the related factors of depression and anxiety.

方法分层整群抽取某医科大学本科生509名进行抑郁、焦虑情绪的流行特征及其相关因素调查分析。

Reproductive health institutions in Suzhou and Jiaxing areas were sampled with stratified sample method.

我国于 1994年就引入生殖健康的概念，并将其作为卫生工作的优先服务项目。

Methods With a questionnaire, a stratified cluster sample of 7 527 students were investigated. Multivariate logistic regression analysis was performed to assess factors for suicidal ideation.

方法采用统一调查表，应用分层整群抽样的方法调查广州市8所中学和8所小学学生7 527名，通过多因素Logistic回归模型筛选自杀意念的危险因素。

Methods A stratified random cluster sample of12637students in32schools were investigated with an anonymous questionnaire.

采用整群抽样的方法，抽取上海市有代表性的32所学校共计12637名大中学生，进行无记名问卷调查。

Methods A questionnaire survey on QOL was conducted to a clustered stratified sample of 2036 students of rural or urban to Hubei.

采用分层整群抽样方法，对湖北省城乡中小学生2036名利用《儿童少年生活质量量表》进行生活质量测查。

Methods By using health related behaviors questionnaire for Chinese youths, a stratified sample of 5158 students from 12 junior middle schools in 4 cities in Henan Province were surveyed. The influencing factors were analyzed.

采用分层整群抽样方法，抽取河南省4个省辖市12所初中的5158名学生，应用中国疾病预防控制中心制定的"中国青少年健康相关行为调查问卷"进行调查，并对影响因素进行分析。

Objective To analyze depression, anxiety and the related psychological social factors, and to provide evidence for the prevention of mental diseases and mental health education. Methods A cluster stratified sample of 509 medical college students were questionnaired on epidemic features and the related factors of depression and anxiety.

目的 分析医学生抑郁、焦虑情绪症状及其相关的心理社会因素，学生心理疾病防治和健康教育工作提供依据方法分层整群抽取某医科大学本科生509名进行抑郁、焦虑情绪的流行特征及其相关因素调查分析。

The sample was stratified by farm size (250-499, 500-999, and 1000 or more acres), and telephone follow-up was used to limit non-response bias.

该样本是由农场规模（250-499，500-999，1000亩以上的分层），电话随访用来限制非反应偏差。

So it was last week in Selma , alabama.

上星期在亚拉巴马州塞尔马市发生的事件也是这样一个转折点。

The group also spearheads various social programs in China.

该组织还带头参与中国的各种社会活动。