1. Sociology and Communication Department, Social Sciences Faculty, Salamanca University , Salamanca, Spain
2. Nursing I Department, Nursing and Medicine Faculty, University of the Basque Country (UPV/EHU) , Leioa, Spain
3. Biocruces Bizkaia Health Research Institute , Barakaldo, Spain
4. Public Health and Epidemiology Research Group, School of Medicine and Health Sciences, Universidad de Alcalá , Alcalá de Henares, Madrid, Spain
5. Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health , Baltimore, Maryland, USA