Association between Paediatric Mild Traumatic Brain Injury and Two-Year Psychiatric Outcomes Largely Explained by Pre-Existing Mental Health Problems
Background Evidence that mild traumatic brain injury (mTBI) causes psychiatric problems in children has been mixed. Investigating this issue has been difficult due to the lack of representative longitudinal data on child mTBI that includes adequate measures of subsequent mental health symptoms and service use in young people. Methods We used data from the ABCD longitudinal cohort study to examine the association between mTBI and psychiatric diagnoses, symptoms, and psychiatric service use in over 11,000 children aged 9-10 at i) baseline, and ii) with new cases of mTBI since baseline and psychiatric outcomes and service use at two-year follow-up. We also compared mTBI cases to a comparison group of participants with orthopaedic injury but without mTBI. Mixed-effects models were used and adjusted for demographic and social covariates, with missing data imputed using random forest multiple imputation. To account for baseline mental health outcomes, we used propensity-score matching to ide