1. Drug Abuse Epidemiology Research Group; IMIM-Institut Hospital del Mar d'Investigacions Mèdiques; Barcelona Spain
2. Public Health Agency of Barcelona; Spain
3. Institute of Biomedical Research Sant Pau; Barcelona Spain
4. Department of Psychobiology and Methodology of Health Sciences; Autonomous University of Barcelona; Bellaterra Spain
5. CIBER en Epidemiología y Salud Pública (CIBERESP); Biomedical Research Centre Network for Epidemiology and Public Health (Spain); Madrid Spain
6. Facultat de Ciències de la Salut de Manresa; Universitat de Vic. Universitat Central de Catalunya (UVicUCC); Av Universitària Manresa Spain