1. Psychosomatic Medicine, Internal Medicine VI, Universitätsklinikum Tübingen, Tübingen, Germany
2. Internal Medicine and Gastroenterology, Helios Klinik Rottweil, Rottweil, Germany
3. Charité Center for Internal Medicine and Dermatology, Department of Psychosomatic Medicine, Charité, Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany