Is the effect of quantified road safety targets sustainable?

Recent studies have shown that the setting of road safety targets is associated with a substantial reduction in road fatalities in the short-term. Although such targets may not themselves be responsible for the reduction in fatalities, they serve as a useful measure of the intention and commitment of road authorities to formulate timely road safety measures that lead to the achievement of the target. A quantified target is regarded as one of the key components of a road safety strategy. However, few studies have examined the degree of commitment and attention of road authorities to such targets in the long-term. In this study, we revisit the effectiveness of the quantified road safety targets set by the Organisation for Economic Co-operation and Development (OECD) countries, but with a different method, time scale, and group of comparison countries. We not only evaluate the associations between quantified targets and road fatality levels, but also measure the changes in the time-series trends in road fatalities over the long-term. The results indicate that all seven treatment countries analyzed experienced desirable changes in the time-series trend in road fatalities during the period under study, which implies an increase in road safety improvement over time.