[1] Columbia Univ, NYSPI, Dept Psychiat, Div Child & Adolescent Psychiat, New York, NY 10032 USA
[2] Turku Univ Hosp, Dept Child Psychiat, Turku, Finland
[3] Univ Tromso, Inst Clin Med, RBUP, N-9001 Tromso, Norway
[4] Univ Kuopio, Dept Child Psychiat, FIN-70211 Kuopio, Finland
[5] Tampere Univ, Dept Child Psychiat, FIN-33101 Tampere, Finland
[6] Tampere Univ Hosp, Tampere, Finland
[7] Oulu Univ, Dept Child Psychiat, Oulu, Finland
[8] Univ Helsinki, Dept Child Psychiat, Helsinki, Finland
[9] Columbia Univ, Sch Publ Hlth, Dept Epidemiol, New York, NY USA