1. Department of Psychiatry, St. Bartholomew's & the Royal London School of Medicine & Dentistry, Academic Unit, East Ham Memorial Hospital, London E7 8QR, UK
2. Psychiatric Clinic, Ernst von Bergmann Klinikum, In der Aue 59-61, D-14480 Potsdam, Germany
3. Department of Social Psychiatry, Freie Universität Berlin, Platanenallee 19, D-14050 Berlin, Germany