[1] Nottingham Univ Hosp NHS Trust, Biomed Res Unit, Natl Inst Hlth Res, Nottingham Digest Dis Biomed Res Unit, E Floor West Block,QMC Campus, Nottingham NG7 2UH, England
[2] Freeman Rd Hosp, Div Hepatobiliary & Transplant Surg, Freeman Rd, Newcastle Upon Tyne NE7 7DN, England
[3] Aarhus Univ Hosp, Dept Hepatol & Gastroenterol & Clin Epidemiol, Aarhus, Denmark
[4] Univ Nottingham, City Hosp, Sch Med, Div Epidemiol & Publ Hlth, Clin Sci Bldg, Nottingham NG5 1PB, England