[1] Univ Leeds, St Jamess Univ Hosp, Leeds Inst Med Res, Leeds, England
[2] Copenhagen Univ Hosp Bispebjerg & Frederiksberg, Abdominalctr K, Copenhagen, Denmark
[3] Univ Birmingham, Inst Appl Hlth Res, Coll Med & Dent Sci, Birmingham B15 2TT, England
[4] Univ Hosp Birmingham NHS Fdn Trust, Dept Trauma & Emergency Gen Surg, Birmingham, England