[1] Univ Bristol, Sch Psychol Sci, Bristol, Avon, England
[2] Lovisenberg Hosp, Nic Waals Inst, Oslo, Norway
[3] Univ Bristol, MRC Integrat Epidemiol Unit, Bristol, Avon, England
[4] Norwegian Inst Publ Hlth, PsychGen Ctr Genet Epidemiol & Mental Hlth, Oslo, Norway