Methods 2279 students in Chengdu sampled by optimum distributing delaminating grouping method were interviewed one-to-one by the trained psychiatrists according to SCID.

• 方法按最优分配分层整群抽样抽出成都地区2279名大中学生，由经过培训及一致性检验的精神科医生根据SCID进行一对一问诊确诊。