1. Department of Internal Medicine, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Korea.
2. Division of Pulmonary, Allergy and Critical Care Medicine, Hallym University Sacred Heart Hospital, Anyang, Korea.
3. Division of Pulmonology and Critical Care Medicine, Department of Internal Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
4. BioMedical Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Korea.
5. Division of Allergy, Pulmonary, and Critical Care Medicine, Department of Internal Medicine, Transplant Research Center, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Korea.
6. Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea.
7. Department of Pulmonary and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
8. Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
9. Department of Critical Care Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
10. Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
11. Division of Critical Care Medicine, Department of Hospital Medicine, Inha Collage of Medicine, Incheon, Korea.
12. Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
13. Division of Allergy and Pulmonary Medicine, Department of Internal Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, Korea.
14. Department of Internal Medicine, Gyeongsang National University Hospital, Jinju, Korea.
15. Department of Internal Medicine, Gyeongsang National University Changwon Hospital, Gyeongsang National University School of Medicine, Changwon, Korea.
16. Division of Pulmonology and Allergy, Department of Internal Medicine, College of Medicine, Yeungnam University and Regional Center for Respiratory Diseases, Yeungnam University Medical Center, Daegu, Korea.
17. Division of Pulmonology and Critical Care Medicine, Wonkwang University Hospital, Iksan, Korea.
18. Division of Pulmonary, and Critical Care Medicine, Department of Internal Medicine, Chonnam National University Hospital, Gwangju, Korea.
19. Department of Pulmonology and Critical Care Medicine, Chosun University Hospital, Gwangju, Korea.
20. Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Chungnam National University College of Medicine, Chungnam National University Hospital, Daejeon, Korea.
21. Department of Internal Medicine, Chungnam National University College of Medicine, Chungnam National University Sejong Hospital, Sejong, Korea.
22. Division of Respiratory and Critical Care Medicine, Department of Internal Medicine, Konyang University Hospital, Daejeon, Korea.
23. Department of Internal Medicine, Jeju National University Hospital, Jeju National University School of Medicine, Jeju, Korea.
24. Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Internal Medicine, Korea University Anam Hospital, Seoul, Korea.