[1] Univ Helsinki, Childrens Hosp, Helsinki Univ Cent Hosp, FIN-00029 Helsinki, Finland
[2] Hebrew Univ Jerusalem, Shaare Zedek Med Ctr, Pediat Gastroenterol Unit, IL-91905 Jerusalem, Israel
[3] Univ Hosp UZ Brussels, Pediat Gastroenterol Unit, Brussels, Belgium
[4] Jagiellonian Univ, Sch Med, Polish Amer Childrens Hosp, Krakow, Poland
[5] Erasmus MC Sophia Childrens Hosp, Pediat Gastroenterol Unit, Rotterdam, Netherlands
[6] Meyer Childrens Hosp, Rambam Med Ctr, Haifa, Israel
[7] Univ Copenhagen, Hvidovre Hosp, Dept Pediat, DK-2650 Hvidovre, Denmark
[8] Univ Munich, Dr von Haunersches Kinderspital, Munich, Germany
[9] Univ Roma La Sapienza, Dept Pediat, Rome, Italy
[10] Tel Aviv Univ, Sheba Med Ctr, Edmon & Lili Safra Childrens Hosp, IL-69978 Tel Aviv, Israel
[11] Univ Naples Federico II, Dept Pediat, Naples, Italy
[12] Med Univ Warsaw, Dept Pediat Gastroenterol & Nutr, Warsaw, Poland
[13] Lovisenberg Diakonale Hosp, Unger Vetlesens Inst, Oslo, Norway
[14] Tel Aviv Univ, Sackler Sch Med, Wolfson Med Ctr, Pediat Gastroenterol Unit, IL-69978 Tel Aviv, Israel
[15] Semmelweis Univ, Dept Pediat 1, H-1085 Budapest, Hungary
[16] Hosp Porto, Dept Pediat, Oporto, Portugal