Background Emotional and behavioural problems in children are common. Research suggests that parenting has an important role to play in helping children to become well-adjusted, and that the first few months and years are especially important. Parenting programmes may have a role to play in improving the emotional and behavioural adjustment of infants and toddlers, and this review examined their effectiveness with parents and carers of young children. Objectives 1. To establish whether group-based parenting programmes are effective in improving the emotional and behavioural adjustment of young children (maximum mean age of three years and 11 months); and 2. To assess whether parenting programmes are effective in the primary prevention of emotional and behavioural problems. Search methods In July 2015 we searched CENTRAL (the Cochrane Library), Ovid MEDLINE, Embase (Ovid), and 10 other databases. We also searched two trial registers and handsearched reference lists of included studies and relevant systematic reviews. Selection criteria Two reviewers independently assessed the records retrieved by the search. We included randomised controlled trials (RCTs) and quasiRCTs of group-based parenting programmes that had used at least one standardised instrument to measure emotional and behavioural adjustment in children. Data collection and analysis One reviewer extracted data and a second reviewer checked the extracted data. We presented the results for each outcome in each study as standardised mean differences (SMDs) with 95% confidence intervals (CIs). Where appropriate, we combined the results in a meta-analysis using a random-effects model. We used the GRADE (Grades of Recommendations, Assessment, Development, and Evaluation) approach to assess the overall quality of the body of evidence for each outcome. Main results We identified 22 RCTs and two quasi-RCTs evaluating the effectiveness of group-based parenting programmes in improving the emotional and behavioural adjustment of children aged up to three years and 11 months (maximum mean age three years 11 months). The total number of participants in the studies were 3161 parents and their young children. Eight studies were conducted in the USA, five in the UK, four in Canada, five in Australia, one in Mexico, and one in Peru. All of the included studies were of behavioural, cognitive-behavioural or videotape modelling parenting programmes. We judged 50% (or more) of the included studies to be at low risk for selection bias, detection bias (observer-reported outcomes), attrition bias, selective reporting bias, and other bias. As it is not possible to blind participants and personnel to the type of intervention in these trials, we judged all studies to have high risk of performance bias. Also, there was a high risk of detection bias in the 20 studies that included parent-reported outcomes. The results provide evidence that group-based parenting programmes reduce overall emotional and behavioural problems (SMD -0.81, 95% CI -1.37 to -0.25; 5 studies, 280 participants, low quality evidence) based on total parent-reported data assessed at postintervention. This result was not, however, maintained when two quasi-RCTs were removed as part of a sensitivity analysis (SMD -0.67, 95% CI -1.43 to 0.09; 3 studies, 221 participants). The results of data from subscales show evidence of reduced total externalising problems (SMD -0.23, 95% CI -0.46 to -0.01; 8 studies, 989 participants, moderate quality evidence). Single study results show very low quality evidence of reductions in externalising problems hyperactivity-inattention subscale (SMD -1.34; 95% CI -2.37 to -0.31; 19 participants), low quality evidence of no effect on total internalising problems (SMD 0.34; 95% CI -0.12 to 0.81; 73 participants), and very low quality evidence of an increase in social skills (SMD 3.59; 95% CI 2.42 to 4.76; 32 participants), based on parent-reported data assessed at postintervention. Results for secondary outcomes, which were alsomeasured using subscales, show an impact on parent-child interaction in terms of reduced negative behaviour (SMD -0.22, 95% CI -0.39 to -0.06; 7 studies, 941 participants, moderate quality evidence), and improved positive behaviour (SMD 0.48, 95% CI 0.17 to 0.79; 4 studies, 173 participants, moderate quality evidence) as rated by independent observers postintervention. No further meta-analyses were possible. Results of subgroup analyses show no evidence for treatment duration (seven weeks or less versus more than eight weeks) and inconclusive evidence for prevention versus treatment interventions. Authors' conclusions The findings of this review, which relate to the broad group of universal and at-risk (targeted) children and parents, provide tentative support for the use of group-based parenting programmes to improve the overall emotional and behavioural adjustment of children with a maximum mean age of three years and 11 months, in the short-term. There is, however, a need for more research regarding the role that these programmes might play in the primary prevention of both emotional and behavioural problems, and their long-term effectiveness.
