1. Department of Internal Medicine, Albert Schweitzer Hospital, Dordrecht
2. Department of Nephrology, Erasmus Medical Center, Rotterdam, Netherlands
3. Department of Nephrology, Academic Medical Center, University of Amsterdam, Amsterdam
4. Department of Public Health, Rotterdam, Netherlands
5. University Medical Center Utrecht;
6. Maasstad Hospital
7. VU University Medical Center, Amsterdam;
8. Catharina Hospital, Eindhoven;
9. Academic Medical Center, Amsterdam;
10. Radboud University Nijmegen Medical Center, Nijmegen;
11. Deventer Hospital, Deventer, Netherlands.