[1] Univ Oxford, Nuffield Dept Med, Translat Gastroenterol Unit, Oxford, England
[2] London Sch Hyg & Trop Med, Clin Trials Unit, London WC1, England
[3] London Sch Hyg & Trop Med, Clin Trials, London WC1, England
[4] Univ Liverpool, Hepatol, Liverpool L69 3BX, Merseyside, England
[5] New Cross Hosp, Gastroenterol, Wolverhampton, W Midlands, England
[6] NHS Blood & Transplant, Transfus, Oxford, England
[7] Univ Leicester, Emergency Med, Leicester, Leics, England