The effects of neighbourhood watch in reducing crime
The main aim of this summary is to give an overview about a systematic review of evaluations of neighbourhood watch based on an updated and extended version of a systematic review conducted for the Campbell Collaboration Crime and Justice Group.
There are a number of implications that can be drawn from this review for future research on the effectiveness of neighbourhood watch. First, the review has drawn attention to the common problem of a relatively small number of good-quality studies in terms of research design. Only 36 evaluations could be included in the narrative review and only 18 could be included in the meta-analysis. Second, it is unclear why evaluations of neighbourhood watch stopped abruptly in the mid 1990s. It is possible that researchers felt that the effectiveness or ineffectiveness of neighbourhood watch had already been established and that there was no need for further investigation. Third, none of the studies was based on random allocation of areas to treatment or control conditions. Instead, all studies were based on some version of a quasi-experimental design because of the difficulties involved in implementing community-based programmes in areas where communities have not requested them. Fourth, a particularly important problem for the current review was that a number of potentially eligible EUCPN Summaries of Systematic Reviews3studies did not report data that were suitable for a meta-analysis. This was either because studies presented the results using an unusual statistical notation or left out the data entirely (e.g. when the results were presented in graphical form only). It would be helpful if published evaluations included, at a minimum, raw data, cell sizes and other relevant information in order to facilitate future meta-analyses. Finally, very few evaluations disaggregated the findings in a way that would show differential effects for subgroups and provide detailed information on the effectiveness of features of the programme. Neighbourhood watch has often been described as one of the most widespread methods of reducing crime supported by governments. The current review provides support for this level of implementation. Existing evaluations, taken together, show that neighbourhood watch is effective in reducing crime. However, little is known about the factors that influence the degree of effectiveness. Governments and those responsible for crime prevention policy should investigate differences between more effective and less effective schemes in order to guide good practice. A nationally co-ordinated programme of research on neighbourhood watch is needed, with different schemes implemented and evaluated in different areas to try to establish which features of schemes are most effective and the optimal conditions for effectiveness.