1. Colorectal Surgical Department, West Middlesex University Hospital, Chelsea and Westminster NHS Foundation Trust, Isleworth, UK
2. Department of Surgery, Sheffield Teaching Hospital NHS Foundation Trust, Sheffield, UK
3. Department of Primary Care and Public Health, Imperial College London, London, UK
4. Consultant General and Colorectal Surgeon, Colorectal Surgical Department, West Middlesex University Hospital, Chelsea and Westminster NHS Foundation Trust, Twickenham Road, Isleworth TW7 6AF, UK
5. * HK Sekhon Inderjit Singh is now affiliated with Royal London Hospital, Barts Health NHS Trust. London, UK