[1] Royal Liverpool Univ Hosp, Liverpool Vasc & Endovasc Serv, Liverpool L9 7AL, Merseyside, England
[2] Aintree Univ Hosp NHS Fdn Trust, Liverpool L9 7AL, Merseyside, England
[3] Univ Crete, Univ Hosp Heraklion, Dept Gen Surg, Iraklion, Greece
[4] Aintree Univ Hosp NHS Fdn Trust, Lib Resource & Informat Ctr, Liverpool, Merseyside, England
[5] Pennine Acute Hosp NHS Trust, Royal Oldham Hosp, Dept Vasc & Endovasc Surg, Manchester, Lancs, England