1. Department of Pneumology, Hospital de la Santa Creu i Sant Pau, Barcelona, Catalonia, Spain
2. Pulmonary Rehabilitation Area, Hospital de la Santa Creu i Sant Pau, Barcelona, Catalonia, Spain
3. Home Pulmonary Rehabilitation Department, Corporación Fisiogestión, Barcelona, Catalonia, Spain
4. Department of Clinical Epidemiology and Public Health, Hospital de la Santa Creu i Sant Pau (IIB Sant Pau), Barcelona, Catalonia, Spain
5. Department of Pediatrics, Obstetrics and Gynecology and Preventive Medicine, Universitat Autònoma de Barcelona, Barcelona, Catalonia, Spain
6. CIBER de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain