1. Department of Medical Sociology, University Clinic Düsseldorf, University of Ulm, Germany
2. Institute for Medical Informatics, Biometry & Epidemiology, University of Ulm, Germany
3. Institute of Medical Epidemiology, Biometry and Informatics, University Hospital of Halle, University of Ulm, Germany
4. Clinic of Cardiology, West-German Heart Center Essen, University Duisburg-Essen, University of Ulm, Germany
5. Department of Medical Sociology, University of Ulm, Germany