M C S Wong1,2, J Huang2, D Weller3, R Jones4. 1. Editor-in-Chief, Hong Kong Medical Journal. 2. Jockey Club School of Public Health and Primary Care, Faculty of Medicine, The Chinese University of Hong Kong. 3. Centre for Population Health Science, The University of Edinburgh, Edinburgh, United Kingdom. 4. School of Population Health and Environmental Science, King's College London, London, United Kingdom.