[1] UCL, Royal Free & Univ Coll Med Sch, Dept Psychiat & Behav Sci, London W1N 8EY, England
[2] Inst Psychiat, London, England
[3] Univ Leicester, Dept Psychiat, Leicester, Leics, England
[4] Off Nat Stat, London, England
[5] S London & Maudsley NHS Trust, London, England
[6] Inst Psychiat, WHO Collaborating Ctr, London, England
[7] Univ Bristol, Div Psychiat, Bristol, Avon, England
[8] Off Natl Stat, London, England