Cost-effectiveness of installing barriers at bridge and cliff sites for suicide prevention in Australia

Importance: Installation of barriers has been shown to reduce suicides. To our knowledge, no studies have evaluated the cost-effectiveness of installing barriers at multiple bridge and cliff sites where suicides are known to occur. Objective: To examine the cost-effectiveness of installing barriers at bridge and cliff sites throughout Australia. Design, Setting, and Participants: This economic evaluation used an economic model to examine the costs, costs saved, and reductions in suicides if barriers were installed across identified bridge and cliff sites over 5 and 10 years. Specific and accessible bridge and cliff sites across Australia that reported 2 or more suicides over a 5-year period were identified for analysis. A partial societal perspective (including intervention costs and monetary value associated with preventing suicide deaths) was adopted in the development of the model. Interventions: Barriers installed at bridge and cliff sites. Main Outcomes and Measures: Primary outcome was return on investment (ROI) comparing cost savings with intervention costs. Secondary outcomes included incremental cost-effectiveness ratio (ICER), comprising the difference in costs between installation of barriers and no installation of barriers divided by the difference in reduction of suicide cases. Uncertainty and sensitivity analyses were undertaken to examine the association of changes in suicide rates with barrier installation, adjustments to the value of statistical life, and changes in maintenance costs of barriers. Results: A total of 7 bridges and 19 cliff sites were included in the model. If barriers were installed at bridge sites, an estimated US $145 million (95% uncertainty interval [UI], $90 to $160 million) could be saved in prevented suicides over 5 years, and US $270 million (95% UI, $176 to $298 million) over 10 years. The estimated ROI ratio for building barriers over 10 years at bridges was 2.4 (95% UI, 1.5 to 2.7); the results for cliff sites were not significant (ROI, 2.0; 95% UI, -1.1 to 3.8). The ICER indicated monetary savings due to averted suicides over the intervention cost for bridges, although evidence for similar savings was not significant for cliffs. Results were robust in all sensitivity analyses except when the value of statistical life-year over 5 or 10 years only was used. Conclusions and Relevance: In an economic analysis, barriers were a cost-effective suicide prevention intervention at bridge sites. Further research is required for cliff sites.