[1] Marien Hosp Witten, Witten, Germany
[2] Univ Milan, Med Sch, Milan, Italy
[3] IRCCS Policlin San Donato, Div Gen & Foregut Surg, Milan, Italy
[4] Agaples Diakonie Clin, Kassel, Germany
[5] IRCCS Policlin San Donato, Hlth Profess Res & Dev Unit, Milan, Italy
[6] King Juan Carlos Univ, King Juan Carlos Univ Hosp, Fac Hlth Sci, Madrid, Spain