1. Institute of Epidemiology and Medical Biometry, ZIBMT, Medical Faculty of Ulm University, Ulm, Germany
2. German Center for Diabetes Research (DZD), Neuherberg, Germany
3. Department of Internal Medicine IV, University Hospital Tübingen, Germany
4. Institute of Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany
5. Division of Endocrinology and Diabetology, Department of Internal Medicine 1, University Hospital Ulm, Ulm, Germany
6. Institute for Clinical Chemistry and Pathobiochemistry, Department for Diagnostic Laboratory Medicine, University Hospital Tübingen, Tübingen, Germany
7. Institute of Health Services Research and Health Economics, Center for Health and Society, Faculty of Medicine, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
8. Institute of Health Services Research and Health Economics, German Diabetes Center (DDZ), Leibniz Centre for Diabetes Research at Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
9. Department of General Practice and Primary Care, University Hospital Ulm, Um, Germany
10. Department of Psychiatry and Psychotherapy II, University Hospital Ulm, Um, Germany
11. Department of Gastroenterology, Klinikum Bayreuth, Medizincampus Oberfranken der Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Bayreuth, Germany
12. Diabetes Center at Sophie-Charlotte-Platz, Diabetes Foot Unit, Berlin, Germany