Aims: A systematic review of studies testing the effectiveness of educational and practice base strategies to increase the involvement of primary health-care practitioners in the treatment of tobacco dependence.

Data sources: MEDLINE, EMBASE, CINAHL and the Cochrane Library (1966-2001). Selection criteria included studies that used randomized or controlled clinical designs, controlled before and after trials and interrupted time-series designs and that presented objective and interpretable measures of practitioners' behaviour and biochemically verified patient quit rates.

Review methods: A meta-analysis, using a random effects model, of 24 programmes identified in 19 trials. Effect sizes were adjusted by inverse variance weights to control for studies' sample sizes.

Findings: Analyses to explain the heterogeneity of effect sizes found that interventions were equally effective in changing practitioners' screening and advice-giving rates and their patients' quit rates. Absolute increases for the intervention above the comparison groups were 15% (95% CI = 7-22) for screening rates, 13% (95% CI = 9-18) for advice-giving rates and 4.7% (95% CI = 2.5-6.9) for biochemically verified patient quit rates. Practitioners in training programmes were effective in changing their patients' quit rates but not their own screening rates; educational interventions were more effective than practice-based interventions. For established practitioners, programmes were effective in changing their screening and advice-giving rates, but not their patients' quit rates; a combination of practice-based and educational interventions were more effective.

Conclusions: Primary health-care practitioners can be engaged in the treatment of tobacco dependence to increase equally their screening and advice-giving rates and their patients' quit rates with outcomes of considerable public health and clinical significance. The provision of educational interventions for practitioners in training in combination with systematic outreach practice-based support for established practitioners is likely to be an effective strategy to increase smoking quit rates throughout primary health care.