"Are More ACEs Always Worse? Exploring Nonlinear Associations with Youth Behavior".

Although it is assumed that more Adverse Childhood Experiences (ACEs) are associated with worse health and social problems, there is a lack of research testing alternative forms of the ACEs-outcome relationship among young people, including whether these associations differ by sex. This study examines whether the assumed dose-response relationship between ACEs and internalizing problems (suicidal ideation/attempts, depression, somatic complaints) and externalizing behaviors (rearrest, readjudication, alcohol use, drug use) is consistently observed or instead demonstrates threshold effects or saturation effects (non-linear patterns) for both male and female adolescents. Administrative data were used from over 23,000 justice-involved youth who completed a community-based Florida Department of Juvenile Justice placement (mean age = 17.0, SD = 1.7, 77.2% male, 32.8% female). Logistic regression models incorporating both linear and quadratic ACE terms were estimated to assess non-linear effects and included interaction terms to test for sex differences. Results revealed curvilinear associations for several outcomes, including recidivism and internalizing symptoms, with diminishing effects at higher ACE levels. Although females reported greater ACE exposure and higher rates of internalizing symptoms, the shape of the ACE-outcome relationships did not differ significantly by sex. These findings challenge assumptions of linearity in ACE research and underscore the importance of modeling threshold or saturation effects. Implications for juvenile justice policy and practice highlight the need for assessment and intervention strategies that are sensitive not only to the amount and type of adversity experienced but also to individual and group differences in vulnerability and response.