1. Department of Pulmonary Medicine, Hospital Clínic, University of Barcelona
2. Fundació de Recerca Clínic Barcelona-Institut d’Investigacions Biomèdiques August Pi i Sunyer (FRCB-IDIBAPS), Barcelona
3. Biomedical Research Networking Center on Respiratory Diseases (CIBERES); Madrid, Spain
4. Department of Physical Therapy, Faculty of Medicine, University of Chile, Santiago, Chile