Yeon-Mok Oh

Department of Pulmonary and Critical Care Medicine, and Clinical Research Center for Chronic Obstructive Airway Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul

Sang Do Lee

Department of Pulmonary and Critical Care Medicine, and Clinical Research Center for Chronic Obstructive Airway Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul

Ji-Hyun Lee

Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam

Yong Bum Park

Department of pulmonary and critical care medicine, Hallym University College of Medicine

Jin Hwa Lee

Department of Internal Medicine, EwhaWomans University School of Medicine, Seoul

Woo Jin Kim

Department of Internal Medicine, Kangwon National University, Chuncheon

Sung-Soon Lee

Department of Internal Medicine, Inje University Ilsan Paik Hospital