BACKGROUND: Mental health problems are common and there is evidence to suggest that the origins of such problems lie in infancy and childhood. In particular, there is evidence from a range of studies to suggest that maternal psychosocial health can have a significant effect on the mother-infant relationship, and that this in turn can have consequences for both the short and long-term psychological health of the child. The use of parenting programmes is increasing in the UK and elsewhere and evidence of their effectiveness in improving outcomes for children has been provided. Evidence is now required of their effectiveness in improving outcomes for mothers. OBJECTIVES: The objective of this review is to address whether group-based parenting programmes are effective in improving maternal psychosocial health including anxiety, depression, and self-esteem. SEARCH STRATEGY: A range of biomedical, social science, educational and general reference electronic databases were searched including MEDLINE, EMBASE CINAHL, PsychLIT, ERIC, ASSIA, Sociofile and the Social Science Citation Index. Other sources of information included the Cochrane Library (SPECTR, CENTRAL), and the National Research Register (NRR). SELECTION CRITERIA: Only randomised controlled trials were included in which participants had been randomly allocated to an experimental and a control group, the latter being a waiting-list, no-treatment or a placebo control group. Studies had to include at least one group-based parenting programme, and one standardised instrument measuring maternal psychosocial health. DATA COLLECTION AND ANALYSIS: A systematic critical appraisal of all included studies was undertaken using a modified version of the Journal of the American Medical Association (JAMA) published criteria. The treatment effect for each outcome in each study was standardised by dividing the mean difference in post-intervention scores for the intervention and treatment group, by the pooled standard deviation, to produce an effect size. Where appropriate the results were then combined in a meta-analysis using a fixed-effect model, and 95% confidence intervals were used to assess the significance of the findings. MAIN RESULTS: A total of 23 studies were included in the original review which was increased to 26 at the first udate (2003). Of these 20 provided sufficient data to calculate effect sizes. The 20 studies provided a total of 64 assessments of outcome on a range of aspects of psychosocial functioning including depression, anxiety, stress, self-esteem, social competence, social support, guilt, mood, automatic thoughts, dyadic adjustment, psychiatric morbidity, irrationality, anger and aggression, mood, attitude, personality, and beliefs. Data sufficient to combine in a meta-analysis existed for only five outcomes (depression; anxiety/stress; self-esteem; social support; and relationship with spouse/marital adjustment). The results of the meta-analyses show statistically significant results favouring the intervention group for depression; anxiety/stress; self-esteem; and relationship with spouse/marital adjustment. The meta-analysis of the social support data showed no evidence of effectiveness. Of the remaining data that it was not possible to combine in a meta-analysis, approximately 22% of the outcomes measured, showed significant differences between the intervention group and the control group. A further 40% showed non-significant differences favouring the intervention group. Approximately one-third of outcomes showed no evidence of effectiveness.A meta-analysis of the follow-up data on three outcomes was also conducted - depression, self-esteem and relationship with spouse/marital adjustment. The results show that there was a continued improvement in self-esteem, depression, and marital adjustment at follow-up, although the latter two findings were not statistically significant. This review has been updated (2003) with the addition of 3 new included studies. A number of additional excluded studies have also been added. There is one additional study awaiting 03) with the addition of 3 new included studies. A number of additional excluded studies have also been added. There is one additional study awaiting assessment and 2 ongoing studies listed for inclusion at a future update of this review. The size of effect for the main outcomes has not been substantially altered by this update. Additional sensitivity analyses to assess the impact of quasi randomised studies on the result have also been added. Where the quasi randomised studies are excluded from the analysis, the result was found to be slightly more conservative. REVIEWER'S CONCLUSIONS: It is suggested that parenting programmes can make a significant contribution to the short-term psychosocial health of mothers. However, there is currently a paucity of evidence concerning whether these results are maintained over time, and the limited follow-up data which are available show equivocal results. This points to the need for further evidence concerning the long-term effectiveness of parenting programmes on maternal mental health. Whilst the results of this review are positive overall, some studies showed no effect. Further research is needed to assess which factors contribute to successful outcomes in these programmes with particular attention being paid to the quality of delivery.These results suggest that parenting programmes have a potential role to play in the promotion of mental health.