1 Department of Pulmonary and Critical Care Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA.
2 American College of Chest Physicians, Glenview, IL. Electronic address: mrosen@chestnet.org.
3 Beijing Hospital, Ministry of Health, Beijing, China.
4 Division of Respirology, Critical Care and Sleep Medicine, University of Saskatchewan, Royal University Hospital, Saskatoon, SK, Canada.
5 First Affiliated Hospital of Guangzhou Medical College, Guangzhou Institute of Respiratory Diseases, Guangzhou, China; Chinese Thoracic Society, Beijing Hospital, Ministry of Health, Beijing Institute of Respiratory Medicine, National Clinical Research Centre for Respiratory Medicine, Beijing, China.