1. Department of Hematology, University Medical Center Utrecht, Utrecht, The Netherlands;
2. Hovon Data Center, Rotterdam, The Netherlands;
3. Department of Hematology, Erasmus Medical Center, Rotterdam, The Netherlands;
4. Department of Hematology, Academic Medical Center, Amsterdam, The Netherlands;
5. Department of Hematology, Vrije Universiteit Medical Center, Amsterdam, The Netherlands;
6. Department of Hematology, Academic Hospital Maastricht, Maastricht, The Netherlands;
7. Radboud University Nijmegen Hospital, Nijmegen, The Netherlands;
8. Meander Medical Center, Amersfoort, The Netherlands; and
9. Antonius Hospital, Nieuwegein, The Netherlands