1. Department of Pulmonary and Critical Care Medicine, Center of Respiratory Medicine, China‐Japan Friendship Hospital Peking University Health Science Center Beijing China
2. Department of Pulmonary and Critical Care Medicine, Center of Respiratory Medicine China‐Japan Friendship Hospital Beijing P.R. China
3. National Center for Respiratory Medicine Beijing China
4. Institute of Respiratory Medicine Chinese Academy of Medical Sciences Beijing China
5. National Clinical Research Center for Respiratory Diseases, WHO Collaborating Centre for Tobacco Cessation and Respiratory Diseases Prevention Beijing China
6. Department of Critical Care Medicine Qilu Hospital of Shandong University (Qingdao) Qingdao China
7. Department of Respiratory and Critical Care Medicine The Second Affiliated Hospital of Chongqing Medical University Chongqing China