1. Vth Department of Medicine, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany;
2. Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria;
3. Synlab Academy, Synlab Holding Deutschland GmbH, Mannheim and Augsburg, Germany;
4. Department of Medicine, Division of Nephrology, Johann Wolfgang Goethe-University, Frankfurt am Main, Germany;
5. UMHealthcare, Frankfurt am Main, Germany