1. Department of Medical Epidemiology and Biostatistics, Karolinska Institutet , Stockholm , Sweden
2. Department of Internal Medicine, Division of Nephrology and Transplantation, Erasmus Medical Center , Rotterdam , The Netherlands
3. Centre Hospitalier de Vichy , Vichy , France
4. Parma University Medical School Hospital , Parma , Italy
5. Hospital Universitario de La Princesa , Madrid , Spain
6. KfH Kidney Center , Erfurt , Germany
7. Hôpital du Valais , Sion , Switzerland
8. Department of Nephrology, FISABIO, Hospital Universitari Doctor Peset, Universitat de València , Valencia , Spain
9. Department of Internal Medicine, Division of Dietetics, Erasmus Medical Center , Rotterdam , The Netherlands