1. Institute of Medical StatisticsInformatics and Epidemiology, University of Cologne, Cologne, Germany
2. Deutsches Ärzteblatt and Deutsches Ärzteblatt International (Journal of the German Medical Association)Deutscher Ärzteverlag, Cologne, Germany
3. Academy for Medical Training and EducationChamber of Physicians North-Rhine, Düsseldorf, Germany
4. Medical Clinic 2Municipal Hospital Cologne-Merheim, University of Cologne, Cologne, Germany