1. University of Heidelberg; Department of General, Visceral and Transplant Surgery; Im Neuenheimer Feld 110 Heidelberg Germany 69120
2. University of Washington/Fred Hutchinson Cancer Research Center; Hematology-Oncology; 1100 Fairview Ave N - D5-100 PO Box 19024 Seattle Washington State USA 98109-1024
3. Medical Center - University of Freiburg; Center for Medical Biometry and Medical Informatics; Stefan-Meier-Str. 26 Freiburg Germany D-79104
4. Medical Center - University of Freiburg; Cochrane Germany; Berliner Allee 29 Freiburg Germany 79110