[1] British Columbia Ctr Subst Use, Vancouver, BC, Canada
[2] Univ British Columbia, Interdisciplinary Studies Grad Program, Vancouver, BC, Canada
[3] Univ British Columbia, Dept Psychiat, Vancouver, BC, Canada
[4] Ctr Hlth Evaluat & Outcome Sci, Vancouver, BC, Canada
[5] Univ British Columbia, Dept Med, Vancouver, BC, Canada
[6] Simon Fraser Univ, Fac Hlth Sci, Burnaby, BC, Canada
[7] Ctr Appl Res Mental Hlth & Addict, Vancouver, BC, Canada
[8] Yale Sch Med, Internal Med, New Haven, CT 06510 USA
[9] Yale Sch Med, Yale Program Addict Med, New Haven, CT 06510 USA