[1] Med Univ Vienna, Dept Internal Med 3, Div Gastroenterol & Hepatol, A-1090 Vienna, Austria
[2] Skaraborgs Hosp, Dept Med, Lidkoping, Sweden
[3] Orebro Univ Hosp, Div Gastroenterol, Dept Med, Orebro, Sweden
[4] Univ Orebro, Sch Hlth & Med Sci, Orebro, Sweden
[5] Lund Univ, Skane Univ Hosp, Dept Gastroenterol, Lund, Sweden
[6] Sahlgrens Univ Hosp, Dept Med, Div Gastroenterol, Gothenburg, Sweden
[7] Karolinska Univ Hosp, Dept Gastroenterol & Hepatol, Stockholm, Sweden
[8] Soder Sjukhuset, Div Gastroenterol, Dept Med, Stockholm, Sweden
[9] Ryhov Hosp, Div Gastroenterol, Dept Med, Jonkoping, Sweden
[10] Hilleroed Hosp, Div Gastroenterol, Hillerod, Denmark
[11] Linkoping Univ, Fac Hlth Sci, Div Gastroenterol & Hepatol, Linkoping, Sweden
[12] Skane Univ Hosp, Dept Gastroenterol, Malmo, Sweden
[13] Orebro Univ Hosp, Clin Epidemiol & Biostat Unit, Orebro, Sweden