1. Oxford Trauma and Emergency Care, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK
2. Emergency Research in Oxford, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
3. Institute of Population Health, University of Liverpool, Liverpool, UK
4. Alder Hey Orthopaedics, Alder Hey Children’s NHS Foundation Trust, Liverpool, UK