1. Department of Internal Medicine, Division of Diabetology, Endocrinology and Nephrology University Hospital Tübingen Tübingen Germany
2. Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Centre Munich at the University of Tübingen Tübingen Germany
3. German Center for Diabetes Research (DZD) Neuherberg Germany
4. Section of Experimental Radiology, Department of Diagnostic and Interventional Radiology University Hospital Tübingen Tübingen Germany
5. German Diabetes Center Leibniz Center for Diabetes Research at Heinrich‐Heine‐University Düsseldorf Düsseldorf Germany
6. Institute for Clinical Chemistry and Pathobiochemistry, Department for Diagnostic Laboratory Medicine University Hospital Tübingen Tübingen Germany
7. Department of Endocrinology and Diabetology, Medical Faculty Heinrich‐Heine‐University and University Hospital Düsseldorf Düsseldorf Germany
8. Division of Endocrinology and Diabetology, Department of Internal Medicine I Ulm University Hospital Ulm Germany