AbstractObjectiveTo identify external causes of unintentional childhood injury presenting to Australian EDs.MethodsSix major paediatric hospitals in four Australian states supplied de‐identified ED data for 2011–2017 on age, sex, attendance time/date, presenting problem, injury diagnosis, triage category and mode of separation. Three hospitals supplied data on external cause and intent of injury. A machine classifier tool was used to supplement the missing external cause coding in the remaining hospitals to enable the compilation of a standardised dataset for childhood injury causes analysis.ResultsA total of 486 762 ED presentations for unintentional injury in children aged 0–14 years were analysed. The leading specified cause of ED presentations was low fall (35.0%) followed by struck/collision with an object (13.8%) with little sex difference observed. Males aged 10–14 years had higher rates of motorcycle, pedal cycle and fire/flame‐related injury and lower rates of horse‐related injury and drug/medicinal substance poisoning compared with females. The leading specified external cause resulting in hospitalisation was low fall (32.2%) followed by struck/collision with an object (11.1%). The injuries with the highest proportion of children being hospitalised were drownings (64.4%), pedestrian (53.4%), motorcycle (52.7%) and horse‐related injuries (50.0%).ConclusionsThis is the first large‐scale study since the 1980s to explore external causes of unintentional childhood injury presenting to Australian paediatric EDs. It demonstrates a hybrid human–machine learning approach to create a standardised database to overcome data deficiencies. The results supplement existing knowledge of hospitalised paediatric injury to better understand the causes of childhood injury by age and sex, which require health service utilisation.