The long-term impact of early-life (first 1000 days of life) socioeconomic conditions: a rapid review

Background Experiences and developmental trajectories in early life (the first 1000 days of life) can shape outcomes across the life course, with downstream effects on education, employment and earnings, involvement with the criminal justice system, health and wellbeing, and patterns of service use. These impacts matter not only for individuals and families, but also because they translate into long-term public costs across multiple sectors (e.g., health and social care, education, welfare, and justice). This rapid review focuses on family income/wealth/resources (income, wealth, poverty, socioeconomic status/position) as an influential risk factor linked to early life (the first 1000 days of life) development and synthesizes evidence on their associations with later “future events” such as educational outcomes, labor market outcomes (employment, earnings), crime/justice outcomes, and service use. The evidence base is spread across disciplines and study designs, and findings are often reported in ways that are difficult to compare across outcome domains. A focused synthesis is therefore needed to consolidate what is known about the longer-term impacts of family income/wealth/resources in a way that is usable for subsequent cost and modelling work that spans multiple outcome domains and policy sectors. Why is it important to do this review This review is important because decision-makers need credible, consolidated evidence on how specific risk factors linked to early life (the first 1000 days of life) translate into later outcomes that drive costs and wellbeing across sectors. Without a clear synthesis, planning and prioritization risk relying on fragmented results from single-domain literatures, making it difficult to judge which outcomes are most affected and where the largest public impacts are likely to fall (e.g., education versus justice versus health/service use). A rapid synthesis on early-life family income/wealth/resources will help clarify (i) which “future events” show the most consistent associations (education, employment/earnings, crime/justice, service use), (ii) which outcomes should be prioritized for costing and long-term modelling, and (iii) where evidence allows, whether impacts differ by key subgroups such as sex/gender and deprivation—supporting analyses that consider inequities as well as averages. This is particularly relevant for building an economic case for early intervention, where modelling inputs often require a cross-sector map of outcome pathways and credible estimates of association.