[1] Univ British Columbia, Dept Family Practice, 5950 Univ Blvd, Vancouver, BC V6T 1Z3, Canada
[2] Univ British Columbia, St Pauls Hosp, Ctr Hlth Evaluat & Outcome Sci, 1081 Burrard St, Vancouver, BC V6Z 1Y6, Canada
[3] Univ British Columbia, Dept Anesthesiol Pharmacol & Therapeut, Therapeut Initiat, 2176 Hlth Sci Mall, Vancouver, BC V6T 1Z3, Canada
[4] Univ Calgary, Cummings Sch Med, 3330 Hosp Dr NW, Calgary, AB T2N 4N1, Canada
[5] British Columbia Ctr Subst Use, 400-1045 Howe St, Vancouver, BC V6Z 2A9, Canada
[6] Univ Coll Dublin, Sch Med, Dublin, Ireland
[7] Univ British Columbia, Fac Med, Dept Med, 2775 Laurel St, Vancouver, BC, Canada
[8] Univ British Columbia, Sch Populat & Publ Hlth, 2206 East Mall, Vancouver, BC V6T 1Z3, Canada
[9] Univ British Columbia, Ctr Hlth Serv & Policy Res, 201-2206 East Mall, Vancouver, BC V6T 1Z3, Canada
[10] Univ British Columbia, Sch Nursing, 211 Wesbrook Mall T201, Vancouver, BC V6T 2B5, Canada
[11] Univ British Columbia, Dept Psychiat, David Strangway Bldg, 5950 Univ Blvd, Vancouver, BC V6T 1Z3, Canada