1. Department of Clinical Epidemiology Aarhus University Hospital Aarhus N Denmark
2. Department of Clinical Medicine Aarhus University Aarhus N Denmark
3. Department of Medicine Clinical Epidemiology Unit & Center for Pharmacoepidemiology Karolinska Institutet Solna Sweden
4. Department of Medicine Østfold Hospital Trust Oslo Norway
5. Department of Hematology Institute of Clinical Medicine University of Oslo Oslo Norway
6. Center for Observational Research Amgen Ltd Uxbridge UK
7. Department of Hematology Odense University Hospital Odense Denmark
8. Center for Observational Research Amgen Inc Thousand Oaks CA USA