[1] Lovisenberg Diakonale Hosp, Dept Psychiat, N-0440 Oslo, Norway
[2] Univ Oslo, Norwegian Ctr Addict Res, Oslo, Norway
[3] Lovisenberg Diakonale Hosp, Dept Res, N-0440 Oslo, Norway
[4] Univ Oslo, Inst Pharmacol, Oslo, Norway
[5] Norwegian Inst Publ Hlth, Oslo, Norway