Violence and schizophrenia: examining the evidence.

Background: It is now accepted that people with schizophrenia are significantly more likely to be violent than other members of the general population. A less acknowledged fact is that the proportion of societal violence attributable to schizophrenia is small.

Aims: To critically examine the epidemiological evidence for the association between violence and schizophrenia and estimate the impact of this association on society.

Method: A selective review of the key literature on the epidemiology of violence and schizophrenia. Population-attributable risks for violence in schizophrenia are calculated from population-based studies.

Results: Most studies confirm the association between violence and schizophrenia. Recent good evidence supports a small but independent association. Comorbid substance abuse considerably increases this risk. The proportion of violent crime in society attributable to schizophrenia consistently falls below 10%.

Conclusions: Less focus on the relative risk and more on the absolute risk of violence posed to society by people with schizophrenia would serve to reduce the associated stigma. Strategies aimed at reducing this small risk require further attention, in particular treatment for substance misuse.