[1] ICO, Canc Control & Prevent Programme, Tobacco Control Unit, Barcelona 08908, Spain
[2] Inst Invest Biomed Bellvitge IDIBELL, Canc Control & Prevent Grp, Barcelona 08908, Spain
[3] Univ Int Catalunya, Sch Med & Hlth Sci, Barcelona 08915, Spain
[4] Univ Int Catalunya, Sch Med & Hlth Sci, Dept Basic Sci, Biostat Unit, Barcelona 08915, Spain
[5] ICO, Nursing Res Unit, Barcelona 08908, Spain
[6] IDIBAPS, Hosp Clin Barcelona, Inst Neurosci, Addict Unit, Barcelona 08036, Spain
[7] Univ Barcelona, Sch Med, Dept Clin Sci, Barcelona 08907, Spain
[8] Univ Barcelona, Dept Methodol Behav Sci, Barcelona, Spain