Effectiveness of Trauma-Focused Interventions in Reducing Externalizing Behaviors Among Traumatized Adolescents: A Systematic Review and Meta-Analysis

Background: Childhood trauma represents a pervasive global concern, originating from diverse adverse experiences such as physical or psychological abuse, neglect, exposure to domestic violence, community violence, and crisis events including war and natural disasters. Despite the existing literature has suggested the effectiveness of trauma-focused interventions in reducing trauma-related symptoms, notably post-traumatic stress disorder, depression, and anxiety. Only few studies have specifically evaluated the effectiveness of such interventions on externalizing behaviors—a prevalent concern among traumatized adolescents. To address this research gap, this systematic review and meta-analysis aims to assess the effectiveness of trauma-focused interventions in reducing externalizing behaviors among traumatized adolescents and to identify key attributes that may influence the effectiveness and outcomes of these interventions.

Methods: This study conducted a comprehensive search across 8 electronic databases, including EBSCO, ERIC, MEDLINE, PubMed, ProQuest, PsycINFO, Scopus, and Web of Science. Inclusion criteria of the studies were: (a) Participants aged 10–19; (b) Participants exhibited trauma symptoms or histories and externalizing behaviors; (c) Quantitative measures should be adopted before and after the treatment; (d) Sufficient data were reported to compute an effect size; (e) Original research, excluding reviews, meta-analyses, and case reports; (f) Studies were published in peer-reviewed journals, dissertations, or theses; (g) Studies were published in English; (h) The research design followed the randomized controlled trial. Following the identification of eligible studies, we performed data extraction, quality appraisal, and statistical analyses. Specifically, statistical analyses included two parts: first, calculating the pooled effect size as a standardized mean difference (SMD) using the inverse-variance method, which assigns weights based on the precision of each study. Forest plots were used to summary the effect sizes of the studies with 95% confidence intervals (CIs). Second, subgroup analyses were conducted using the Q statistic and the I² statistic to investigate the sources of heterogeneity.

Results: A total number of 12 studies were finally included. By systematically reviewing the included studies, we identified trauma-focused interventions—such as Trauma-Focused Cognitive Behavioral Therapy, Narrative Exposure Therapy, Prolonged Exposure Therapy, MASTR/EMDR therapy, and Cognitive Processing Therapy—as effective approaches for reducing externalizing behaviors in traumatized adolescents. Results of meta-analysis showed a significant effect of trauma-focused interventions in reducing externalizing behaviors (SMD = - 0.70, 95% CI [- 0.98, -0.41], Z = 4.74, p < 0.001). Subgroup analyses identified several key factors moderating the effectiveness of interventions, including adolescent age, intervention duration, intervention methods, participant number, and intervention settings.

Implications: Our research findings suggest trauma-focused interventions are effective in reducing externalizing behaviors among traumatized adolescents. However, due to the limited number of included studies, further research is needed to evaluate the effectiveness of these interventions comprehensively. Besides, factors such as adolescent age, intervention duration, intervention methods, participant number, and intervention settings should be carefully considered when implementing these interventions in the future.