Methods A structured questionnaire survey was conducted among 2237 university students and senior high school students based on community selected by stratified cluster sampling in Tongzhou district.

 
  • 方法采用整群分层抽样方法,对2237名大、中学生进行艾滋病知识、态度、行为问卷调查。
今日热词
目录 附录 查词历史