"RESULTS: Immediately following bicycle helmet legislation, the rate of bicycle fatalities per 1?000?000 population reduced by 46% relative to the pre-legislation trend [95% confidence interval (CI): 31, 58]. For the period 1990-2016, we estimate 1332 fewer cycling fatalities (95% CI: 1201, 1463) or an average of 49.4 per year (95% CI: 44.5, 54.2). Reductions were also observed for pedestrian fatalities; however, bicycle fatalities declined by 36% relative to pedestrian fatalities (95% CI: 12, 54).

"CONCLUSIONS: In the absence of robust evidence showing a decline in cycling exposure following helmet legislation or other confounding factors, the reduction in Australian bicycle-related fatality appears to be primarily due to increased helmet use and not other factors."