[1] Univ Sherbrooke, Fac Med & Sci Sante, Programmes Toxicomanie, Longueuil, PQ J4K 5G4, Canada
[2] McGill Univ, Joint Dept Epidemiol Biostat & Occupat Hlth, Montreal, PQ, Canada
[3] Direct Sante Publ Montreal, Montreal, PQ, Canada
[4] Inst Natl Sante Publ Quebec, Montreal, PQ, Canada
[5] CHU Laval, Unite Rech Sante Populat, Quebec City, PQ G1V 4G2, Canada
[6] Univ Laval, Dept Med Sociale & Prevent, Quebec City, PQ, Canada
[7] Univ Montreal, Dept Social & Prevent Med, Montreal, PQ, Canada