Randomised controlled trial of a parenting intervention in the voluntary sector for reducing child conduct problems: outcomes and mechanisms of change

BACKGROUND: To test effectiveness of a parenting intervention, delivered in a community-based voluntary-sector organisation, for reducing conduct problems in clinically-referred children. METHODS: Randomised controlled trial, follow-up at 6, 18 months, assessors blind to treatment status. Participants--76 children referred for conduct problems, aged 2-9, primarily low-income families, randomised to treatment vs. 6-month wait-list group. Retention was 93% at 6 months, 90% at 18 months. Interventions--Webster-Stratton Incredible Years video-based 14-week group programme, teaches cognitive-behavioural principles for managing behaviour, using a collaborative, practical, problem-solving approach. Primary outcomes--child problem behaviour by parent-report (Eyberg) and home-based direct observation; secondary outcomes--observed positive and negative parenting; parent-reported parenting skill, confidence and depression. RESULTS: Post-treatment improvements were found in child problem behaviour, by parent-report (effect size (ES) .48, p = .05) and direct observation (ES .78, p = .02); child independent play (ES .77, p = .003); observed negative (ES .74, p = .003) and positive (ES .38, p = .04) parenting; parent-reported confidence (ES .40, p = .03) and skill (ES .65, p =.01), using ANCOVA to control for baseline scores. Maternal depression did not change. Consumer satisfaction was high. At 18-month follow-up, although no randomised comparison was possible, changes appeared to maintain, with no significant change toward baseline level on any measure. Change in observed positive parenting appeared to mediate change in child problem behaviour (p < .025). CONCLUSIONS: Findings suggest that a group-based cognitive-behavioural parenting programme, delivered by well-trained and supervised staff, can be effective in a community voluntary-sector setting, for reducing conduct problems and enhancing parenting skills. Change in parenting skill appears to be a key mechanism for change in child behaviour. Findings have implications for feasibility of translating evidence-based programmes, even for clinically-referred conduct problems, into less specialised community settings, likely to have lower costs and be more accessible for families.