Objectives: A meta-analysis was conducted to determine the average effect size of internalizing and externalizing symptoms after pediatric traumatic brain injury across a range of severity (mild, moderate, and severe). Two-meta-regressions were also conducted to determine the role of age at injury at time since injury on these effect sizes.Participants and Methods: 9725 titles and abstracts were collected from PubMed, PsycInfo, and Web of Science. Of these, 63 full-text articles were examined for inclusion criteria to determine eligibility for the study. To be included, the studies needed to be published prior to March 2017 in English, needed to have a control group of either orthopedically injured or typically developing peers, and required a reliable and valuable measure of internalizing and externalizing symptoms in children. Studies were excluded for non-accidental head injuries or if the sample recruited was outside the range of 2-17 years old at the time of injury. The analysis was based on 16 studies including 1083 cases of mild TBI, 184 cases of moderate TBI, 214 cases of severe TBI, and 1605 control cases.Results: Analyses revealed a large effect size for internalizing symptoms of children with mild TBI (Hedge<'>s g = -0.624, p = 0.009), a small effect size for moderate TBI (Hedge<'>s g = -0.238, p = 0.029), and a large effect size for severe TBI (Hedge<'>s g = -0.923, p < .001). These findings indicate that parents rate children<'>s internalizing symptoms more severely for brain injured children than for typically developing or non-brain injured peers. These children may be experiencing more severe symptoms such as anxiety and depression regardless of injury severity. For externalizing symptoms, analyses demonstrated a moderate effect size for mild TBI (Hedge<'>s g = -0.531, p = 0.003), a small effect size for moderate TBI (Hedge<'>s g = -0.257, p = 0.007), and a large effect size for severe TBI (Hedge<'>s g = -0.909, p < .001). Thus, children who experienced a TBI demonstrated externalizing symptoms including hyperactivity and impulsivity with the largest effect size associated with severe TBI. The results of the meta-regressions indicated that only injury severity was a significant predictor of symptom severity.Conclusions: Using meta-analytic methods, we found that children who experience traumatic brain injury are rated as exhibiting more severe internalizing and externalizing symptoms across levels of severity. This effect was largest for severe injury and smallest for moderate injury. Caregivers and healthcare practitioners can use this information to better screen for and treat internalizing and externalizing symptoms in children after a traumatic brain injury.



College and Department

Family, Home, and Social Sciences; Psychology



Date Submitted


Document Type





pediatric, traumatic brain injury, psychiatric symptoms, internalizing, externalizing