1. Department of Infectious Diseases and Sexual Health, Trinity Centre, Trinity Road, Bradford BD5 0JD
2. The John Goligher Department of Colorectal Surgery
3. Department of Genitourinary Medicine, The General Infirmary at Leeds, Great George Street, Leeds LS1 3EX
4. St James Institute of Oncology, St James University Hospital, Beckett Street, Leeds LS9 7TF, UK