1. Respiratory Department, San Pedro de Alcántara Hospital, Cáceres, Spain
2. CIBER de enfermedades respiratorias (CIBERES), Madrid, Spain
3. Instituto Universitario de Investigación Biosanitaria de Extremadura (INUBE)
4. Institut de Recerca Biomédica de Lleida (IRBLLEIDA), Lleida, Spain
5. Division of Pulmonary and Sleep Medicine, Bethesda North Hospital, Cincinnati, Ohio
6. Cardiology Department, San Pedro de Alcántara Hospital, Cáceres, Spain
7. Respiratory Department, Virgen del Puerto Hospital, Plasencia, Cáceres, Spain
8. Unidad Médico-Quirúrgica de Enfermedades Respiratorias, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío, Sevilla, Spain
9. Respiratory Department, University Hospital, Burgos, Spain
10. Respiratory Department, IIS Fundación Jiménez Díaz, Madrid, Spain
11. Respiratory Department, Valdecilla Hospital, Santander, Spain
12. Respiratory Department, Gregorio Marañón Hospital, Madrid, Spain
13. Respiratory Department, Miguel Servet Hospital, Zaragoza, Spain
14. Respiratory Department, Vall d'Hebron Hospital, Barcelona, Spain
15. Respiratory Department, Doce de Octubre Hospital, Madrid, Spain
16. Respiratory Department, San Juan Hospital, Alicante, Spain
17. Respiratory Department, Alava University Hospital IRB, Vitoria, Spain
18. Nursing Department, Extremadura University, Cáceres, Spain
19. Medicine/Pulmonary and Critical Care, University of Chicago, IL