1. Department of Internal Medicine, Cantonal Hospital Frauenfeld, Frauenfeld, Switzerland
2. Center for Laboratory Medicine, St. Gallen, Switzerland
3. Center for Sleep Medicine, Department of Pneumology and Sleep Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland
4. Department of Internal Medicine, Infectious Diseases and Hospital Epidemiology, Cantonal Hospital Münsterlingen, Münsterlingen, Switzerland