1. Emergency Service, University Hospital of La Paz P. of Castellana, 261, 28046 Madrid, Spain
2. Primary Care Research Unit of Salamanca (APISAL), Health Centre of San Juan, Av. Portugal 83, 37005 Salamanca, Spain
3. Institute of Biomedical Research of Salamanca (IBSAL), 37007 Salamanca, Spain
4. Faculty of Nursing and Physiotherapy, Universidad de Salamanca, 37007 Salamanca, Spain
5. Department of Statistics, University of Salamanca, 37008 Salamanca, Spain
6. Department of Hematology, University Hospital of Salamanca, 37008 Salamanca, Spain
7. Primary Healthcare Management, Castilla y León Regional Health Authority (SACyL), 37007 Salamanca, Spain
8. Research Network on Chronicity, Primary Care and Health Promotion (RICAPPS), 37005 Salamanca, Spain
9. Department of Medicine, University of Salamanca, 37007 Salamanca, Spain
10. Department of Biomedical and Diagnostic Sciences, University of Salamanca, 37007 Salamanca, Spain
11. Home Hospitalization Service, Marqués of Valdecilla University Hospital, 39008 Santander, Spain