[1] Humanitas Univ, Dept Biomed Sci, Pieve Emanuele, Italy
[2] IRCCS, Endoscopy Unit, Humanitas Clin & Res Ctr, Rozzano, Italy
[3] Valduce Hosp, Gastroenterol Dept, Como, Italy
[4] Univ Oslo, Clin Effectiveness Res Grp, Oslo, Norway
[5] Showa Univ, Northern Yokohama Hosp, Digest Dis Ctr, Yokohama, Japan
[6] Human Res Hosp & Univ, Via Manzoni 56, I-20089 Rozzano, Milano, Italy