Prevalence of Traumatic Brain Injury in Detained Youth: Associations With Aggression, Violent Charges, and Behavioral Infractions

Objective: Youth involved in the legal system have markedly higher exposure to traumatic brain injury (TBI), yet limited research has examined how TBI relates to specific behavioral outcomes in this population. This preregistered study estimated TBI prevalence in detained youth and investigated associations between TBI dimensions (severity, frequency) and aggression form (physical, verbal) and function (reactive, proactive), violent charges, and facility-recorded behavioral infractions. Setting: Two state-funded juvenile detention centers in the Midwest US. Participants: 252 youth (80.95% male, ages 10-17) enrolled between 2022 and 2023. Design: Cross-sectional study of consecutively admitted youth. Main Measures: TBI history was assessed via self-report, with severity indexed by loss of consciousness (LOC) duration (<30 minutes: mild; >30 minutes: moderate/severe). Youth also completed the Proactive and Reactive Aggression Questionnaire and the Buss-Perry Aggression Questionnaire, and facility records provided information on violent charges and behavioral infractions. Group differences were tested using chi-square tests, t tests, Welch’s t tests, and Wilcoxon rank-sum tests, with a preregistered family-wise alpha of.01. Results: TBI prevalence was 42.06%, with 23.41% reporting multiple TBIs. Among those with TBI, 63% reported LOC, and 14 youth (13.21%) were classified as moderate/severe. Youth with any TBI reported significantly higher physical aggression (Cohen d = 0.46, P = .001). Associations with verbal aggression (d = 0.25, P = .08) and reactive aggression (d = 0.29, P = .02) trended in the same direction but did not meet the preregistered threshold, while proactive aggression showed no association (r = 0.01, P = .83). No significant associations were found between TBI and violent legal charges or behavioral infractions. Conclusions: TBI is common among detained youth and is selectively associated with elevated physical aggression. Routine TBI screening at intake and interventions targeting impulse control and emotion regulation may improve outcomes for this high-risk population.