[1] Guys Kings & St Thomas Med Sch, Sect Child & Adolescent Psychiat, London, England
[2] Guildhall Univ, Dept Psychol, London, England
[3] Inst Psychiat, MRC, Child Psychiat Unit, London SE5 8AF, England
[4] Inst Psychiat, Social Genet & Dev Psychiat Ctr, London, England