Intervention against smoking among boys in urban junior middle schools in China
We conducted a study between April and October 1996 on the smoking behaviour of 3300 boys, selected by random cluster sampling, in junior middle schools in four cities in China. We divided the boys randomly into three groups: general intervention, high-intensity intervention and controls. The study consisted of three sessions of investigation, comprising individual interviews and small group discussions, and two stages of intervention. The procedure of practice—summary—re-practice—re-summary was adopted in order to find an effective intervention method. The data were analysed with Epi-Info and SAS software, and effectiveness of the intervention was evaluated by matched analysis.