1. Department of Respiratory Medicine, Ohara Healthcare Foundation , Kurashiki Central Hospital , Okayama , Japan
2. Department of Emergency and Critical Care Medicine, Graduate School of Biomedical & Health Sciences , Hiroshima University , Hiroshima , Japan
3. Center for General Medicine Education , Keio University School of Medicine , Tokyo , Japan
4. Department of Emergency Medicine and Critical Care Medicine , St. Marianna University School of Medicine , Kanagawa , Japan
5. Department of Respiratory Medicine and Infectious Diseases , Oita University Faculty of Medicine , Oita , Japan
6. Department of Medicine , Division of General Internal and Emergency Medicine , Aarau , Switzerland
7. Faculty of Medicine , University of Basel , Basel , Switzerland