1. Department of Haematology; Leiden University Medical Centre; Leiden the Netherlands
2. Department of Haematology; University Medical Centre Groningen; Groningen the Netherlands
3. Department of Medical Statistics; Leiden University Medical Centre; Leiden the Netherlands
4. Department of Haematology; Medisch Spectrum Twente; Enschede the Netherlands
5. Department of Haematology; Antonius Ziekenhuis Nieuwegein; Nieuwegein the Netherlands
6. Department of Haematology; VU Medical Centre; Amsterdam the Netherlands
7. Department of Haematology; Erasmus Medical Centre; Rotterdam the Netherlands
8. Department of Haematology; University Medical Centre Nijmegen; Nijmegen the Netherlands
9. Department of Haematology; University Medical Centre Utrecht; Utrecht the Netherlands
10. Department of Haematology; Amsterdam Medical Centre; Amsterdam the Netherlands