1. Department of Thrombosis and Hemostasis; Leiden University Medical Center; Leiden the Netherlands
2. Department of Clinical Epidemiology; Leiden University Medical Center; Leiden the Netherlands
3. Department of Internal Medicine; Hospital General Universitario Gregorio Marañón; Madrid Spain
4. Department of Internal Medicine; Hospital Municipal de Badalona; Barcelona Spain
5. Department of Internal Medicine; Hospital Clínico San Carlos; Madrid Spain