[1] British Columbia Ctr Subst Use, 1045 Howe St,Suite 400, Vancouver, BC V6Z 2A9, Canada
[2] Univ British Columbia, Dept Med, 317-2194 Hlth Sci Mall, Vancouver, BC V6T 1Z3, Canada
[3] Brown Univ, Sch Publ Hlth, 121 S Main St, Providence, RI 02903 USA
[4] PHS Community Serv, 9 E Hastings St, Vancouver, BC V6A 1M9, Canada
[5] Yale Sch Med, Program Addict Med, 333 Cedar St, New Haven, CT 06510 USA
[6] Yale Sch Med, Gen Internal Med, 333 Cedar St, New Haven, CT 06510 USA