1. Department of Dermatology, Maastricht University Medical Center, Maastricht, The Netherlands;
2. Department of Dermatology, Amphia Hospital, Breda, The Netherlands;
3. Department of Internal Medicine, Laboratory for Clinical Thrombosis and Haemostasis, Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands;
4. Department of Dermatology, Kolbach kliniek, Maastricht, The Netherlands;
5. Department of Epidemiology, Maastricht University Medical Center, Maastricht, The Netherlands