[1] Univ Manchester, Neurosci & Psychiat Unit, Manchester, Lancs, England
[2] Univ Glasgow, Fac Med, Div Community Based Sci, Glasgow, Lanark, Scotland
[3] Gartnavel Royal Hosp, Dept Psychiat, Glasgow G12 0YN, Lanark, Scotland
[4] Univ Edinburgh, Royal Edinburgh Hosp, Dept Psychiat, Edinburgh EH10 5HF, Midlothian, Scotland
[5] Univ Oxford, Univ Dept Psychiat, Oxford, England