1. Academic Medical Centre; Amsterdam; the Netherlands
2. Leiden University Medical Centre; Leiden; the Netherlands
3. University Medical Centre Groningen; Groningen; the Netherlands
4. Ikazia Hospital; Rotterdam; the Netherlands
5. Haga Hospital; The Hague; the Netherlands
6. Meander Medical Centre; Amersfoort; the Netherlands
7. Diakonessen Hospital; Utrecht; the Netherlands
8. Amphia Hospital; Breda; the Netherlands
9. Medical Centre Leeuwarden; Leeuwarden; the Netherlands
10. Maxima Medical Centre; Veldhoven; the Netherlands
11. Jeroen Bosch Hospital; ‘s-Hertogenbosch; the Netherlands
12. Maastricht University Medical Centre; Maastricht; the Netherlands
13. University Medical Centre St Radboud; Nijmegen; the Netherlands