1. Department of Clinical Research and Epidemiology, Comprehensive Heart Failure Center, University Hospital Würzburg, Am Schwarzenberg 15 , 97080 Würzburg , Germany
2. Department of Medicine I, University Hospital Würzburg , Würzburg , Germany
3. Department of Health, Medicine and Caring Sciences, Linköping University , 581 83 Linköping , Sweden
4. Department of Cardiology, Cardiovascular Center Bad Neustadt/Saale , Von-Guttenberg-Straße 11, 97616 Bad Neustadt an der Saale , Germany
5. Department of General Internal Medicine and Psychosomatics, University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
6. Department of General Practice and Health Services Research, University Hospital Heidelberg, Im Neuenheimer Feld 130.3, 69120 Heidelberg, Germany