[1] Karolinska Inst, Dept Med, Stockholm, Sweden
[2] Karolinska Inst, Dept Med Epidemiol & Biostat, Stockholm, Sweden
[3] Univ Ctr Gastrointestinal & Liver Dis, Dept Gastroenterol & Hepatol, Basel, Switzerland
[4] Orebro Univ Hosp, Dept Pediat, Orebro, Sweden
[5] Columbia Univ, Dept Med, Coll Phys & Surg, New York, NY USA
[6] Karolinska Univ Hosp, Dept Upper GI, Div Hepatol, Stockholm, Sweden
[7] Karolinska Inst, Dept Med, C1 77, S-14186 Stockholm, Sweden