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. Department I of Internal Medicine, Centre of Integrated Oncology Aachen Bonn Cologne Duesseldorf; Faculty of Medicine and University Hospital of Cologne, University of Cologne; Cologne Germany
3. Max-Planck Institute for the Biology of Ageing; Cologne Germany
4. German Leukemia & Lymphoma Patients' Association; Bonn Germany
5. 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
6. Department of Epidemiology; Johns Hopkins Bloomberg School of Public Health; Baltimore Maryland USA
7. University of New Mexico Comprehensive Cancer Center; University of New Mexico Health Sciences Center; Albuquerque NM USA