1. Institute of Health and Social Care, London South Bank University , London, UK
2. Centre for Health Services Research, School of Health & Psychological Sciences, City, University of London , London, UK
3. East London NHS Foundation Trust , London, UK
4. University Hospitals Sussex NHS Trust , Brighton, UK
5. University College London Great Ormond Street Institute of Child Health, University College London , London, UK
6. Centre for Adolescent Rheumatology Versus Arthritis at University College London Great Ormond Street Institute of Child Health, University College London , London, UK
7. National Institute for Health Research Biomedical Research Centre at Great Ormond Street Hospital , London, UK