1. 1Faculty of Health, Camilo José Cela University, Madrid, Spain;
2. 2Foundation for Biosanitary Research and Innovation in Primary Care, Madrid, Spain;
3. 3Intensive Care Unit, Bellvtige University Hospital, L’Hospitalet de Llobregat, Barcelona, Spain;
4. 4International Committee of the Red Cross, Caracas, Venezuela;
5. 5Pneumology Department, Puerta de Hierro Hospital, Madrid, Spain;
6. 6Preventive Medicine Department, Virgen de la Salud Hospital, Toledo, Spain