Children entering foster care are at high risk of poor mental health. In this single-blind, cluster-randomized phase 3 trial, 382 families with 488 0–5-year-old children, entering foster care, were randomized 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 children and to their birth and foster families, aiming to improve child mental health and recommend return home or adoption. The principal outcome was child mental health, as measured by the Strengths and Difficulties Questionnaire Total Difficulties (SDQ-TD) scale at 2.5 years after study entry. In total, 286 families (149 NIM and 137 SAU, 367 children) were followed-up (79.4%). Intention-to-treat analysis found no intervention effect of NIM: mean (s.d.) SDQ-TD NIM, 11.5 (7.6); SAU, 11.1 (7.2); adjusted mean difference (NIM − SAU), 1.4; 95% confidence interval (−0.63, 3.53); P = 0.17. No within-trial effects for primary or secondary outcomes were observed. Despite its components being delivered to a high standard, the UK legal context surrounding NIM led to it being impossible to deliver to all eligible families, and less than 70% of families received the intervention to which they were randomized. Future research will be required to evaluate NIM in more favorable social and legal contexts. ClinicalTrials.gov registration: NCT02653716.

进入寄养家庭的儿童心理健康状况不佳的风险很高。在这项单盲、整群随机的 3 期试验中，382 个家庭和 488 名 0-5 岁儿童进入寄养家庭，被随机分配到新奥尔良干预模型 （NIM） 或照常社会工作服务 （SAU）。NIM 为儿童及其出生和寄养家庭提供婴儿心理健康评估（~3 个月）和治疗（6-9 个月），旨在改善儿童心理健康并建议回家或收养。主要结局是儿童心理健康，在研究开始后 2.5 年通过优势和困难问卷总困难 （SDQ-TD） 量表测量。总共对 286 个家庭 （149 个 NIM 和 137 个 SAU，367 名儿童） 进行了随访 （79.4%）。意向治疗分析发现 NIM 没有干预效果： 平均值 （s.d.） SDQ-TD NIM，11.5 （7.6）;SAU，11.1 （7.2）;调整后均数差 （NIM − SAU），1.4;95% 置信区间 （-0.63， 3.53）;P = 0.17。未观察到对主要或次要结局的试验内影响。尽管其组成部分以高标准交付，但英国围绕 NIM 的法律背景导致无法将其交付给所有符合条件的家庭，并且只有不到 70% 的家庭接受了他们被随机分配的干预。需要未来的研究在更有利的社会和法律背景下评估 NIM。ClinicalTrials.gov 注册：NCT02653716。