title: Tobacco and alcohol prevention: preliminary results of a four-year study.
mesh_terms: D000293:Adolescent; D000437:Alcoholism / Q000517:prevention & control*; D003479:Curriculum; D005500:Follow-Up Studies; D006266:Health Education; D006801:Humans; D010379:Peer Group; D012008:Recurrence; D012306:Risk; D000074606:Smoking Prevention; D012931:Social Environment