1. Internal Medicine, National Hospital Organization Nishi-Beppu Hospital, Beppu, Japan;
2. Respiratory Medicine and Infectious Diseases, Oita University Faculty of Medicine, Yufu, Japan;
3. Department of Medical Safety Management, Oita University Faculty of Medicine, Yufu, Japan;
4. Department of Radiology, Kansai Rosai Hospital, Amagasaki, Japan