Objective: To systematically review all RCTs of behavioral interventions to prevent children (age 5-12) and adolescents (age 13-18) start smoking, or quit if they have started.

Methods: EMBASE 1974- ; MEDLINE 1966- ; ERIC 1964- ; HEALTH 1975-AND PSYCHLIT 1974- were searched using the terms and variations smoking cessation; smoking; smoker; tobacco; nicotine (cessation or quit or stop or prevent); abstain or reduce; tobacco use disorder; ex-smoker; freedom from smoking; anti-smoke; conditioning therapy; (counsel or supportive or advice); health promotion; exp health education; (education or prevent or promotion); exp psychotherapy, group; group adj2 therapy; exp behavior therapy; adolescent behavior; and terms for RCT.

Results: To date 45 RCTs with N => 30 in each subgroup with biochemical validation of non-smoking have been identified. Definitions of smoking range between daily to one cigarette per month. Interventions include smoking and social influences refusal skills, discussion of health effects, contracting, self-improvement, decision making, anxiety reduction, biofeedback, and stress management. Average reductions in new onset of smoking in the studies analysed to date are 10% over a year, but in those studies which assessed smoking rates six years beyond the original programme, no changes in smoking rates are demonstrated.

Discussion: Programmes using behavioural interventions need to offer repeated booster sessions throughout the period of maximum risk for commencing smoking (age 8-18).