The analysis shows that in 2007, in Cardiff, where this collaborative approach was pioneered, the scheme lopped off almost £7 million from health, societal, and criminal justice costs caused by violence.
The estimated individual and societal costs of violence recorded by the police in England and Wales in 2003-4 came to £14 billion.
The Cardiff Violence Prevention Programme, which was set up in 2003, entails the capture of anonymised information on violent incidents treated in hospital emergency departments.
This information includes exactly where the incident took place, the time, day, and weapon used. These data are then fed to a crime analyst who combines them with police intelligence to come up with continuously updated crime hotspot maps.
The police and local councils use these maps to target prevention activities more precisely than is possible using police intelligence alone, including redirecting resources, changing police patrol routes, changing the licensing conditions of particular establishments, intervening in other locations, such as street violence hotspots, schools and parks, and the positioning of surveillance cameras.
The Cardiff data has also led to other prevention strategies in the city, including the weekend pedestrianisation of certain areas of the centre where bars and clubs cluster, and the mandatory use of plastic barware.
The analysis drew on monthly data for hospital admissions and serious woundings and minor (common assaults) recorded by the police in Cardiff and 14 other comparable cities in England and Wales between 2001 and 2007, which included the two years preceding the introduction of the scheme.
The economic impact of violence was based on implementation costs and Home Office figures, taking account of inflation and other relevant factors.
Although the numbers of common assaults rose between 2003 and 2007 - a reflection of earlier and more frequent police intervention resulting from use of A&E data - the number of more costly serious woundings fell in Cardiff.
This added up to a yearly saving of £5 million until 2007, when the savings rose to £6.9 million, including savings of £1.25 million in healthcare costs and £1.62 million in criminal justice system costs.
The costs of setting up and running the scheme were, modest, however, coming in at just under £108,000, and just over £210,000, respectively. In all, the scheme has saved a total of £82 for every £1 spent on it.
"[Our] study builds on a growing literature showing that violence-prevention strategies can provide a substantial return on investment, and demonstrates the benefits of multiagency information-sharing partnerships to guide violence prevention planning, policies, and activities," write the authors.
"Moreover, the fact that the reduction in woundings and the benefit-cost savings were documented at the community level underscores the public health significance of the [Cardiff] model," they add.
Journal
Injury Prevention