[1] Royal Coll Surgeons England, Clin Effectiveness Unit, London, England
[2] Hull York Med Sch, Kingston Upon Hull, England
[3] London Sch Hyg & Trop Med, Dept Hlth Serv Res & Policy, London, England
[4] Cambridge Univ Hosp NHS Trust, Cambridge Vasc Unit, Cambridge, England
[5] Hull Univ Teaching Hosp NHS Trust, Acad Vasc Surg Unit, Kingston Upon Hull, England
[6] Freeman Rd Hosp, Dept Intervent Radiol, Newcastle Upon Tyne, England
[7] Royal Stoke Univ Hosp, Staffordshire & South Cheshire Vasc Network, Stoke On Trent, England
[8] Royal Coll Surgeons England, Clin Effectiveness Unit, 38-43 Lincolns Inn Fields, London WC2A 3PE, England