Background Maltreated children are at high risk of negative psychosocial outcomes. Interventions targeting their foster carers are modestly effective. No previous RCT has targeted birth families of maltreated children in foster care.
Methods In this single-blind, cluster-randomised, phase 3 trial (Registration: BeST? Clinicaltrials.gov: NCT02653716), families with a 0-5-year-old child entering foster care in Glasgow or London were randomised 1:1 (secure web portal; researchers masked; stratification by site with minimisation) to the New Orleans intervention model (NIM) or social work services-as-usual (SAU). NIM offers infant mental health assessment (~3 months) and treatment (6-9 months) to birth families and children in foster care, aiming to improve child mental health and recommend return home or adoption. The principal outcome measure of child mental health was the 20-item Strengths and Difficulties Total Difficulties (SDQ-TD) Scale at 2.5 years post study entry (high scores indicating poorer child behaviour).
Findings Between January 2012 and July 2021, 382 families (488 children) were recruited: 22 families were later deemed non-eligible leaving 360 families (439 children; 47.0% female). Follow-up continued until December 2023 when the trial was fully powered: 286 families (149 NIM; 137 SAU, 367 children) were followed up at 2.5 years (79.4%). Intention-to-treat analysis found no intervention effect of NIM: Mean (SD) SDQ-TD NIM 11.5 (7.6); SAU 11.1 (7.2); adjusted mean difference (NIM-SAU) 1.4; 95% CI (-0.63, 3.53); p=0.17. Girls randomised to NIM had higher SDQ-TD scores at 2.5 years wrt SAU: Interaction p=0.0217; adjusted mean difference 2.96; (0.12, 5.82); p= 0.042 - adjusted mean difference in boys was 0.12; 95% CI (-2.82, 3.09). Of 52 SAEs (21 NIM; 31 SAU), none were intervention related. Within the trial time horizon, NIM is not cost-effective costing £10,592 per child versus £4557 for SAU.
Interpretation Contextual challenges meant only 66.4% of eligible families received NIM. Despite no measured within-trial effects for SDQ-TD, higher scores in girls randomised to NIM could indicate either poorer mental health or, conversely, a process of recovery. Follow-up is therefore essential.
Funding National Institute for Health Research (PHR 12/211/54)