[1] Ctr Clin Documentat & Evaluat SKDE, Tromso, Norway
[2] UiT Arctic Univ Norway, Dept Community Med, Tromso, Norway
[3] Oslo Univ Hosp, Nydalen DPS, Oslo, Norway
[4] Innlandet Hosp Trust, Norwegian Natl Advisory Unit Concurrent Subst Abu, Hamar, Norway
[5] UiT Arctic Univ Norway, Fac Hlth Sci, Dept Clin Med, Tromso, Norway
[6] Norwegian Inst Publ Hlth, Dept Mental Disorders, Oslo, Norway
[7] Univ Oslo, Inst Clin Med, Oslo, Norway
[8] Univ Oslo, Inst Hlth & Soc, Oslo, Norway
[9] Univ Oslo, Dept Psychol, Oslo, Norway
[10] Univ Oslo, Sch Pharm, PharmacoEpidemiol & Drug Safety Res Grp, Oslo, Norway
[11] Karolinska Inst, Dept Med Epidemiol & Biostat, Stockholm, Sweden
[12] Univ Hosp North Norway, Div Mental Hlth & Subst Abuse, Tromso, Norway