1. Division of Surgery and Interventional Science; University College London; London UK
2. Department of Urology; Northwick Park Hospital; London UK
3. Department of Primary Care Medicine; Faculty of Medicine; University of Malaya; Kuala Lumpur Malaysia
4. Department of Medicine; Royal Free Hospital; London UK
5. Department of Epidemiology and Public Health; Health Behaviour Research Centre; University College London; London UK
6. UCL Cancer Institute; London UK
7. Surgical & Interventional Trials Unit; University College London; London UK
8. Department of Urology; University College London Hospital; London UK