1. Department of Neuropsychiatry, University of Concepcion, Concepcion, Chile
2. Senior Registrar in Psychiatry, Whitely Wood Clinic, Sheffield
3. Consultant Forensic Scientist and Associate of the University of Sheffield, Rampton Hospital, Retford, Notts DN22 0PD
4. Professor of Psychiatry, University of Sheffield, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF