1. Pneumology and Thoracic Surgery Service University Hospital Nuestra Señora de Candelaria Santa Cruz de Tenerife Spain
2. Pneumology Service University Hospital Lucus Augusti Lugo Spain
3. Division of Clinical Epidemiology and Biostatistics, Research Unit University Hospital Nuestra Señora de la Candelaria (HUNSC) and Primary Care Management Santa Cruz de Tenerife Spain