[Mentally ill patients--a danger?]

This paper reviews the current state of the debate on the relationship between mental disorder and violent behaviour. Starting from the discussion of methodological approaches to assessing a possible association, the most important studies carried out on the issue in recent years are discussed. Their results concur in supporting the assumption that there is a moderate but reliable association between mental disorder and violence. However, this does not imply that people with mental illness are generally more likely to commit violent acts than members of the general population. An elevated risk of violent behaviour is only evident for specific psychiatric diagnoses and for particular symptom constellations. For schizophrenia and other psychotic disorders, a significant increase in the likelihood to commit violent acts is reported. Substance use disorder and antisocial personality disorder, however, represent a markedly higher risk for violent behaviour. The article further discusses possible determinant of violent behaviour such as psychotic symptoms and comorbidity with substance abuse, and considers who is at particular risk of becoming a target of violent acts.