1. Gesundheitszentrum St. Gallen, St. Gallen, Switzerland
2. Institute of General Practice and Health Services Research, University of Zurich, Zurich, Switzerland
3. Departement Medizin, Klinik für Innere Medizin, Kantonsspital Winterthur, Winterthur, Switzerland
4. Radio Oncology, University Hospital, Basel, Switzerland