1. Division of Pulmonology and Critical Care Medicine, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, Republic of Korea
2. Department of Oncology, Asan Medical Centre, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
3. Department of Internal Medicine, Chonnam National University Medical School and Hwasun Hospital, Gwangju 58128, Republic of Korea
4. Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
5. Department of Internal Medicine, Pusan National University Yangsan Hospital, Yangsan 50612, Republic of Korea
6. Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu 41404, Republic of Korea
7. Division of Pulmonology, Allergy and Critical Care Medicine, Department of Internal Medicine, Pusan National University Hospital, Busan 49241, Republic of Korea
8. Division of Pulmonology, Department of Internal Medicine, Chungnam National University, Daejeon 34134, Republic of Korea
9. Division of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, Yeouido St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul 16247, Republic of Korea
10. Departments of Internal Medicine, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 05030, Republic of Korea
11. Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Internal Medicine, Korea University Guro Hospital, Korea University College of Medicine, Seoul 08308, Republic of Korea
12. Division of Pulmonology, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul 16247, Republic of Korea
13. Department of Internal Medicine, Inha University Hospital, Incheon 22332, Republic of Korea