[1] Federico II Univ Naples, Sch Med, Publ Hlth Dept, Naples, Italy
[2] Univ Salerno, Dept Med Surg & Dent, Gastrointestinal Unit, Salerno, Italy
[3] Sapienza Univ Rome, Dept Surg Sci, Rome, Italy
[4] Flinders Univ S Australia, Adelaide, SA, Australia
[5] Med Univ Vienna, Dept Gen Surg, Div Visceral Surg, Vienna, Austria
[6] Gastroobesoctr Inst, Sao Paulo, Brazil
[7] Harvard Med Sch, Brigham & Womens Hosp, Boston, MA USA