ObjectiveTo explore the evidence for interventions that integrate child health and social care and support programmes and the impact they have on child health and wellbeing.Data sourcesThe Cochrane Library, Ovid Medline, Ovid Embase, Ovid Emcare, Ovid Health Management Information Consortium (HMIC) database, and Ovid Social Policy and Practice, Proquest Psychinfo and Ebscohost Cinahl.EligibilityPeer-reviewed original research that described an intervention integrating health care and social support or care interventions for children and young people (CYP) up to the age of 18 years in high-income countries. All databases were searched from inception to August 2023.Data extraction and synthesis16 studies were identified: 4 RCTs, 5 quantitative studies, 5 qualitative studies and 2 mixed methods studies. A narrative review and quality check of included studies was performed. Study heterogeneity meant a meta-analysis could not be completed.ResultsFive qualitative, five quantitative, two mixed methods and four randomised controlled trials were included. We identified three main models of delivering integrated health and social care services: targeted support for vulnerable groups, where the provision of packages of interventions focussed on target populations showed potential for decreasing the need for social support in the long-term but with limited evidence for reducing referrals into other services. They were more successful in meeting specific objectives such as lower rates of smoking, and reducing repeat pregnancies; collaborative health and social support were typically collocated services which improved collaborative working but with little impact on workload, job satisfaction, or service delivery; and school centred health and social care, which improved some aspects of CYP wellbeing and physical health but with concerns they added to teacher workload.ConclusionsIntegrated health and social support programmes offer promising solutions to addressing health inequity in children and young people in underserved populations. However, more robust and consistent study designs are needed to guide researchers and policy makers in their implementation and evaluation.What is already known on this topic.Integrated care that is equipped to mitigate at least some of the social determinants of health is considered key to improving health inequalities in children and young people in underserved populations.Despite increasing investment in integrating health and social support there is little evidence of which models of delivery are most effective in which circumstances nor of the precise impact on target groups and the wider healthcare system.What this study addsWe identified three models of integrating health and social support: Packages of interventions targeted at specific groups; Collaborative (and collocated) health and social support; and School-centered health and social care interventions.Results across the three models offered promise of improved care and support for the underserved, referral rates into other services tended to be lower and packages interventions achieved positive results for specific objectives. However, findings were inconsistent, drop-out rates were high, and there are concerns over sustainability without sufficient resources.How this study might affect research, practice and policyEmbedding iterative co-production in future research and interventions could improve engagement and outcomes and it’s important that further works explores their cost effectiveness and implications for other elements of health and care services.Appropriate resources and a longer-term commitment to promoting integrated health and social support is needed to fully understand the strengths and weaknesses of the offer and maximise the potential benefits.