Protocol for a systematic review and meta-analysis of long-term neurocognitive outcomes in paediatric traumatic brain injury

INTRODUCTION: Children who suffer from traumatic brain injury (TBI) are at risk of permanent brain damage and developmental deficits. Reports on neurodevelopmental outcomes in paediatric TBI suffer from small sample size and varying outcome definitions in the neurocognitive domains tested. This protocol describes a systematic review and meta-analysis of paediatric TBI in the following key neurocognitive domains: executive function, perceptual–motor function, language, learning and memory, social cognition and complex attention. METHODS: A comprehensive search comprising studies from Medline, Cochrane, Embase and PsycINFO published from 1988 to 2019 will be conducted. We will include studies on children ≤18 years old who suffer from mild, moderate and severe TBI as determined by the Glasgow Coma Scale that report neurocognitive outcomes in domains predetermined by the Diagnostic and Statistical Manual of Mental Disorders fifth edition criteria. Systematic reviews, meta-analyses, randomised controlled trials, case–control, cohort and cross-sectional studies will be included. References from systematic reviews and meta-analyses will be hand-searched for relevant articles. A meta-analysis will be performed and effect sizes will be calculated to summarise the magnitude of change in each neurocognitive domain compared at different timepoints and stratified by severity of TBI. Included studies will be pooled using pooled standardised mean differences with a random effects model to determine an overall effect. In the scenario that we are unable to pool the studies, we will perform a narrative analysis. ETHICS AND DISSEMINATION: Ethics approval is not required for this study. The authors of this study will publish and present the findings in a peer-reviewed journal as well as national and international conferences. The results of this study will provide understanding into the association between different severities of paediatric TBI and long-term neurocognitive outcomes. PROSPERO REGISTRATION NUMBER: CRD42020152680.