The effectiveness of anonymised information sharing and use in health service, police, and local government partnership for preventing violence related injury

The objective of the study was to evaluate the effectiveness of anonymised information sharing to prevent injury related to violence.

Although it was all categories of violence with which our study was concerned (alcohol related, public space, domestic, violence in which children are injured, violence in the work place and in parks and schools etc.), alcohol-related violence was the largest component. The work of the partnership is therefore as much concerned with tackling alcohol misuse as it is with tackling violence.

In 2008-9, police recorded over 900 000 violent incidents in England and Wales, representing 1643 violent incidents per 100 000 population; the murder rate was 1.1 per 100 000 population. In the United Kingdom, interpersonal violence in 2003-4 resulted in medical and lost productivity costs of £2.1bn (2.3bn Euros; $3.3bn) and £1.7bn, respectively. Efforts at preventing violence can be implemented at individual, relationship, and community levels. As cultures of violence are often developed and reinforced at the community level, prevention strategies implemented at this level can reach large groups of individuals at risk. There are, however, few scientific evaluations of violence prevention programmes at the community level.

After a 33 month development period, anonymised data relevant to violence prevention (precise violence location, time, days, and weapons) from patients attending emergency departments in Cardiff and reporting injury from violence were shared over 51 months with police and local authority partners and used to target resources for violence prevention.

Uniquely in Cardiff and throughout this study, data derived from the emergency departments relevant to targeted violence prevention were combined with police data and used to deploy prevention resources. This prototype partnership met about every six weeks and, based on the combined data, introduced and sustained a range of strategies designed to address specific risks and patterns observed in the data. These strategies comprised repeated adjustments to the routes of police patrols and moving police resources from the suburbs to the city centre at weekends to ensure that police were present and able to intervene at specific locations and times identified by the data, targeting problematic licensed premises (by police and city government officials responsible for alcohol licensing) and informing public space deployment of closed circuit television (CCTV).

Over the course of the intervention period, the partnership initiated and coordinated violence prevention initiatives. Prevention strategies unrelated to targeted policing were also implemented by the City Council, prompted by the combined data and other factors such as the need to improve traffic flow and public transport arrangements. These included pedestrianising sections of a city centre street where bars and nightclubs are mainly concentrated (February 2004), mandatory use of plastic glassware in selected licensed premises (after 2005) and more frequent late night public transport services (from February 2004).

The unique characteristics of the partnership that were not present in any other UK city partnership during the period of the evaluation were the systematic collection, summary, and use of emergency department data for violence prevention and the participation of emergency department and maxillofacial clinicians in statutory partnership meetings. It's important to realise that this violence prevention partnership work is carried out under the aegis of a statutory partnership (a result of the Crime and Disorder Act). Local authorities are statutory partners. The City Council therefore co-owns all the strategies listed in the BMJ paper.

The main outcome measures were drawn from records of hospital admissions related to violence and police records of woundings and less serious assaults in Cardiff and other cities after adjustment for potential confounders.

Information sharing and use were associated with a substantial and significant reduction in hospital admissions related to violence. In Cardiff City rates fell from seven to five a month per 100 000 population compared with an increase from five to eight in comparison cities (adjusted incidence rate ratio 0.58, 95% confidence interval 0.49 to 0.69). Average rate of woundings recorded by the police changed from 54 to 82 a month per 100 000 population in Cardiff compared with an increase from 54 to 114 in comparison cities (adjusted incidence rate ratio 0.68, 0.61 to 0.75). There was a significant increase in less serious assaults recorded by the police, from 15 to 20 a month per 100 000 population in Cardiff compared with a decrease from 42 to 33 in comparison cities (adjusted incidence rate ratio 1.38, 1.13 to 1.70).

The graphs of rates of violence in the supporting material suggest that, after a period of about two years in which rates in the intervention city and comparison cities diverged, steady state was reached and differential rates were maintained thereafter. This suggests that effectiveness increased as the partners learned how to process data efficiently and to deliver prevention based on the combined data and that this learning became embedded in practice.

The City Council's written licensing policy has been influenced by these A&E data; licensing officials from the local authority are members of the violence prevention partnership as is the chairman of the Cardiff licensing magistrates. The five year policy is currently being revised; the new one is being formulated in the light of these data. Since health became a responsible authority under the terms of the amended Licensing Act, these data have become even more influential - and have been used by public health consultants in licensing hearings and to formulate new cumulative impact polices.

Two innovations which the partnership is taking forward are the collection and use for managing licensed premises of data on where drunk people attending A&E or the alcohol treatment centre obtained their last drink (on the basis that serving a drunk person is illegal); and an alcohol treatment centre (drunk tank) which we found reduces burdens on A&E.

Our findings suggest that communities can achieve substantial reductions in the public health burden of violence through organised data driven partnerships between health, law enforcement agencies, and local government. Four barriers were overcome in the course of the project:

• (Unfounded) concerns about confidentiality with regard to sharing data from A&Es. These were overcome with reference to the Information Commissioner who repeatedly advised that there are no barriers to A&Es and NHS Trusts sharing anonymised data on violence locations and weapons for violence prevention purposes. The IC has advised successive governments similarly.
• Difficulties scaling up this approach across England. Prompted by a structured adoption campaign, the coalition government and its predecessor made the use of data from A&E to tackle violence a priority, published a new information standard, and made the collection of this information by NHS Trusts a contractual obligation.
• Sustaining partnership work has been challenging in the context of fierce cost cutting. This was overcome by lobbying the local authority and the local Police Commissioner who as a result maintained the essential analytical capability, and by persuading the NHS Trust (Cardiff and Vale University Health Board) to pick up the administrative support.
• Embedding data collection in the work of A&E receptionists. This was overcome by including training on this data recording in standard receptionist training, by making the A&E reception supervisor a member of the partnership group, by feeding back to receptionists the outcomes of using the data they collect and share, and by nominating the senior receptionist for a community safety award for this work - presented by the chief constable.

Further reading:

Florence C, Shepherd J, Brennan I, et al. Inj Prev doi:10.1136/injuryprev-2012-040622

Florence C, Shepherd J et al. BMJ 2011;342:d3313 doi:10.1136/bmj.d3313

Warburton A L, Shepherd J, Emerg Med J2006; 23:12-17. DOI 10.1136/EMJ.2004.023028