[1] Karolinska Inst, Huddinge Univ Hosp, Dept Gastroenterol & Hepatol, S-14186 Huddinge, Sweden
[2] Karolinska Inst, Karolinska Hosp, Dept Med, Clin Epidemiol Unit, Huddinge, Sweden
[3] Sahlgrens Univ Hosp, Dept Med, S-41345 Gothenburg, Sweden
[4] Soder Sjukhuset, Dept Surg, Stockholm, Sweden
[5] Univ Hosp, Dept Gastroenterol & Hepatol, Uppsala, Sweden
[6] Univ Hosp, Dept Med, Sect Gastroenterol & Hepatol, Umea, Sweden
[7] Karolinska Hosp & Inst, Dept Gastroenterol & Hepatol, Stockholm, Sweden
[8] Univ Hosp, Dept Gastroenterol & Hepatol, Malmo, Sweden
[9] Univ Hosp, Dept Gastroenterol & Hepatol, Lund, Sweden
[10] Med Ctr Hosp, Dept Med, Div Gastroenterol & Hepatol, Orebro, Sweden
[11] Univ Hosp, Div Gastroenterol & Hepatol, Linkoping, Sweden
[12] Karolinska Inst, Dept Med Epidemiol, Stockholm, Sweden