Annual Research Review: Mapping the multifaceted approaches and impacts of adverse childhood experiences - an umbrella review of meta-analyses.

Adverse childhood experiences (ACEs) significantly impact lifelong health and well-being. Despite extensive research, a comprehensive understanding of ACEs' multifaceted impacts continues to be challenging to achieve. This study synthesizes meta-analytic evidence to provide a comprehensive view of ACEs' effects, addressing various approaches to conceptualizing ACEs and their diverse outcomes. Employing an umbrella synthesis methodology, this review integrated findings from 99 meta-analyses involving 592 effect sizes. We examined ACEs through specificity, lumping, dimensional, and child maltreatment-centric approaches, assessing their impact across six domains: biological system dysregulation, neuropsychological impairments, physical health complications, mental health conditions, social and behavioral challenges, and criminal justice involvement. The findings reveal a small to moderate overall effect size of ACEs across outcome domains. Specific ACE approaches exhibited varying impact levels, with notable differences in effects on mental health, social/behavioral issues, and criminal justice involvement. When ACEs were aggregated without distinguishing between different types, but with consideration of their cumulative effects, adverse outcomes were significantly exacerbated. The child maltreatment-centric approach consistently demonstrated substantial effects across all evaluated domains. This review underscores the heterogeneity in ACEs' impacts, influenced by the type of ACE and specific outcomes considered. It highlights the necessity for comprehensive approaches to understanding, preventing, and mitigating the effects of ACEs. These insights are vital for developing targeted interventions and informing policy-making, emphasizing the complexity and varied nature of ACEs' influence on individual development and societal well-being.