1. Hematology Department, Hospital Clínico San Carlos Universidad Complutense, Madrid, Spain
2. Hematology Department, Hospital de Cruces, Bilbao, Spain
3. Hematology Department, Hospital Juan Canalejo, Coruña, Spain
4. Hematology Department, Complejo Hospitalario Universitario Vigo, Xeral Cíes, Vigo, Spain
5. Hematology Department, Hospital Arnau de Vilanova, Valencia, Spain
6. Hematology Department, Hospital Universitario de Salamanca, Salamanca, Spain
7. Hematology Department, Hospital Duran i Reynals, ICO Barcelona, Spain
8. Hematology Department, Hospital Santa Creu i Sant Pau, Barcelona, Spain
9. Hematology Department, Hospital Universitario Central de Asturias, Oviedo, Spain
10. Medical Department, Amgen SA, Barcelona, Spain on behalf of the Spanish Erythropathology Group