分层抽样,分组抽样
Methods After group sampling 1 181 parents were investigated on their attitude and practice of sexual health education in 4 districts of Harbin by questionnaire.
方法通过分层抽样的方法,对哈尔滨市4个地区1181名家长对孩子家庭性教育的态度、行为等进行问卷调查。
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