1. Cochrane Haematology, Department I of Internal Medicine, Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf; Faculty of Medicine and University Hospital Cologne, University of Cologne; Cologne Germany
2. Faculty of Medicine and University Hospital Cologne, University of Cologne; Department I of Internal Medicine, Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf, Cochrane Haematology; Cologne Germany
3. Institute for Evidence in Medicine (for Cochrane Germany Foundation); Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg; Freiburg Germany