1. School of Respiratory Therapy, College of Medicine, Taipei Medical University Taipei Taiwan
2. Center of Thoracic Medicine Taipei Medical University Taipei Taiwan
3. Department of Thoracic Medicine Taipei Medical University Hospital Taipei Taiwan
4. Department of Thoracic Medicine Chang Gung Memorial Hospital Taipei Taiwan
5. Airway Disease Section, National Heart and Lung Institute, Imperial College London London United Kingdom
6. Royal Brompton and Harefield Hospitals London United Kingdom
7. College of Medicine, Taipei Medical University Taipei Taiwan