Medicine (Baltimore) 2015 Sep;94(38):e1614
From the Clinic for Gastroenterology and Hepatology, University Hospital of Cologne, Kerpener Str. 62, Köln, Germany (HV, NH, HJ, SA, BA, KF, DM, PA, SS, TU, ND, SHM); Institute of Medical Statistics, Informatics and Epidemiology, University of Cologne, Kerpener Str. 62, Köln, Germany (HM).