1. Institute for Health Services Research and Health Economics, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
2. Institute for Health Services Research and Health Economics, Centre for Health and Society, Medicine and University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
3. German Center for Diabetes Research, Partner Düsseldorf, München-Neuherberg, Germany
4. Department of Health Services Research, CAPHRI Care and Public Health Research Institute, Maastricht University, Maastricht, The Netherlands
5. Specialized Diabetes Practice Leverkusen, Leverkusen, Germany
6. Research Institute Diabetes Academy Mergentheim (FIDAM), Bad Mergentheim, Germany
7. Diabetes Center Mergentheim, Bad Mergentheim, Germany
8. Department of Clinical Psychology, University of Bamberg, Bamberg, Germany