This review found that structural interventions at suicide hotspots averted suicide at these sites. Some increases in suicide were evident at neighbouring sites but there was an overall reduction in all suicides by jumping. These conclusions reflect the evidence presented but there was variation between studies and adoption of methods of suicide other than jumping was unknown.

To assess the effectiveness of structural interventions at suicide hotspots in the prevention of suicide.

MEDLINE, PsycINFO and Scopus were searched in July 2012. Search terms were presented. Reference lists of key review papers were searched for additional studies.

Eligible studies had to focus on an intervention that involved installation of barriers or equivalent structural measures designed to prevent suicide by jumping from a height. Before and after intervention data on suicides by jumping from the site had to be provided.

Studies were conducted in UK, USA, Canada, New Zealand and Switzerland. Most studies assessed the effect of barriers installed on bridges or viaducts. Fencing off-road access to cliffs and installation of a safety net were evaluated.

Two reviewers independently assessed studies for inclusion in the review.

The authors did not state that they assessed quality.

Pre- and post-intervention counts of suicides at the site of the intervention and exposure time in years were extracted from included studies. Equivalent information for other jumping sites in the same city (where reported) were extracted. Authors were contacted for additional information where necessary.

The authors did not state how many reviewers were involved in data extraction for the review.

Studies were combined using meta-analysis techniques with methods used to account for varying exposure periods to the intervention and values of zero. Effect sizes were calculated for the change in the expected number of suicides following the installation of the structural intervention. The same modelling approach was used to estimate the effect of the intervention on suicides at nearby jumping sites and the net overall effect on suicides by jumping. Statistical heterogeneity was assessed using the median incident rate ratio.

Nine studies were included in the review.

Pre-intervention there were 436 deaths over 77 study years at the jumping sites (mean of 5.7 deaths per year). Post-intervention there were 21 deaths over 46.4 study years (mean of 0.5 deaths per year).

Adjusting for study differences, there was a reduction in jumping suicides per year at the sites with structural interventions of 86% (95% CI 79% to 91%). There was an increase in jumping suicides per year at nearby sites of 44% (95% CI 15% to 81%). The net gain was a reduction in all jumping suicides of 28% (95% CI 13% to 40%).

There was evidence of study heterogeneity in all three analyses.

Structural interventions at suicide hotspots avert suicide at these sites. Some increases in suicide are evident at neighbouring sites but there is an overall reduction in all suicides by jumping.

This review was based on defined inclusion criteria and a search of a small range of databases. Study quality was not assessed. Two reviewers were involved in study selection for the review; it was unclear whether procedures to minimise bias and error were adopted for data extraction. Methods of analysis appeared to be appropriate.

The conclusions reflect the evidence presented. However, it should be borne in mind that other strategies (such as telephone crisis lines) may have been in place in addition to barriers and the impact of these is unknown, there was evidence of heterogeneity between studies and adoption of other methods of suicide is unknown. These limitations were all acknowledged by the authors.

Practice: The authors recommended that restricting access to suicide jump sites be given careful consideration among other suicide prevention activities in cities around the world. New structures could be designed to incorporate barriers in an aesthetically pleasing way or designed for such modifications should they become necessary.

Research: The authors stated that the effectiveness of interventions other than structural barriers at suicide hotspots (such as telephone crisis lines) should be explored. Learning from those who have made suicide attempts or been prevented from doing so at particular sites would be informative.

Australian Government Department of Health and Ageing.

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.