1. University Hospital of Cologne; Institute of Medical Statistics, Informatics and Epidemiology; Kerpener Str. 62 Cologne Germany 50937
2. University Hospital of Cologne; Department I of Internal Medicine, Center of Integrated Oncology Köln Bonn; Cologne Germany 50924
3. University Hospital of Cologne; Cochrane Haematological Malignancies Group, Department I of Internal Medicine; Kerpener Str. 62 Cologne Germany 50924
4. University Hospital of Cologne; Department I of Internal Medicine; Kerpener Str. 62 Cologne Germany 50924