1. Institute of Preventive Medicine and Public Health, Faculty of Medicine, University of Lisbon, Lisbon, Portugal
2. Centro de Investigação e Estudos de Sociologia (CIES-IUL), Instituto Universitario de Lisboa (ISCTE-IUL), Lisboa, Portugal
3. Institut National de la Santé et de la Recherche Médicale, Le Kremlin Bicêtre, France