1. Institute of Epidemiology and Medical Biometry, Central Institute for Biomedical Technology, German Center for Diabetes Research (DZD), University of Ulm, Albert-Einstein-Allee 41, 89081 Ulm, Germany
2. Division of Endocrinology & Metabolism, Department of Internal Medicine I, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany
3. Medical Clinic, Health Center Spaichingen, Diabetes Center, Hospital District Tuttlingen, Robert Koch Straße 31, 78549 Spaichingen, Germany
4. 2nd Department of Internal Medicine, General Hospital Linz, Krankenhausstraße 9, 4021 Linz, Austria
5. Department of Internal Medicine, Academic Hospital Paul Gerhardt Stift, Martin Luther University of Halle-Wittenberg, Paul-Gerhardt-Straße 42-45, 06886 Lutherstadt Wittenberg, Germany
6. 2nd Department of Internal Medicine, Clinical Center HELIOS Hildesheim, Senator-Braun-Allee 33, 31135 Hildesheim, Germany
7. Department of Diabetes, Clinical Center Dortmund GmbH, Beurhausstraße 40, 44137 Dortmund, Germany
8. Department of General Internal Medicine, Endocrinology and Diabetes, HELIOS Clinic Schwerin, Wismarsche Straße 393-397, 19049 Schwerin, Germany