A review of effective interventions for reducing aggression and violence.

This paper addresses the question of whether individual violence can be reduced in frequency or severity, if so to what extent and by which methods. It opens with a brief overview of the nature of personal violence and discussion of some key definitional and methodological problems. However, its principal focus is on the findings obtained from a series of meta-analytic reviews of structured programmes for adolescents and adults who have shown repeated aggression or been convicted of personal violence, drawing together the results of studies conducted in prison, probation, youth justice and allied services. Additional results are considered from a systematic review of studies of violence prevention among offenders with mental disorders. This incorporates the preliminary findings of a meta-analysis of controlled trials of psychosocial interventions with that population. Overall, it is concluded that there is sufficient evidence currently available to substantiate the claim that personal violence can be reduced by psychosocial interventions, but that much more research is required to delineate the parameters of effectiveness in this context. Proposals are made for future investigations with reference to the theoretical understanding of causal relationships and the design of experimental trials.