1. San Pedro de Alcantara Hospital, Caceres, Spain
2. CIBER de enfermedades respiratorias (CIBERES), Madrid, Spain
3. Bio-Araba Research Institute; Álava University Hospital, Vitoria, Spain
4. Valdecilla Hospital, Santander, Spain
5. General Universitario Hospital, Alicante, Spain
6. Belvitge Hospital, Barcelona, Spain
7. Son Dureta Hospital, Palma de Mallorca, Spain
8. San Juan Hospital, Alicante, Spain
9. Las Palmas de Gran Canaria University, Las Palmas de Gran Canaria, Spain
10. Clinic Hospital, Barcelona, Spain