Global Road Traffic Safety Disparities: Regional Trends and Longitudinal Evidence

Road traffic injury remains a persistent public-health and transport-planning challenge, sitting at the intersection of transportation safety, urban policy, and intelligent transportation systems (ITS). This study reanalyzes open, country-level panel data from World Health Organization Sustainable Development Goal (SDG) indicator 3.6.1, distributed by Our World in Data, to characterize the evolution of road traffic death rates across 182 countries at five time points, 174 of which carry an assigned United Nations SDG region. The analysis combines descriptive statistics, a paired-samples t-test and Wilcoxon signed-rank test, a linear mixed-effects model with a Year × Region interaction and a random intercept for country (re-estimated with an additional random slope for Year as a robustness check), OLS trend estimation, three dispersion indices (Gini coefficient, interquartile range, and coefficient of variation), and sensitivity analyses excluding zero-valued, extreme, and small-island observations. The world-aggregate death rate declined 12.1%, and country-level rates fell significantly (paired t(181) = −3.67, p < 0.001, Cohen’s dz = 0.27), unchanged in sensitivity analysis (dz = 0.31). The improvement was highly uneven, however: a mixed-effects model with a Year × Region interaction fit significantly better than a main-effects-only model (likelihood-ratio χ2(6) = 103.98, p < 0.001), and the interaction remained significant when country-specific slopes were also modeled (χ2(6) = 41.62, p < 0.001). In population-weighted regional aggregates, Europe and Northern America and Australia and New Zealand recorded reductions exceeding 44%, whereas Sub-Saharan Africa, Central and Southern Asia, and Latin America and the Caribbean declined by less than 9% and Northern Africa and Western Asia rose slightly (+1.2%). Global dispersion widened on every measure: the Gini coefficient rose from 0.241 to 0.353. The observed regional and temporal patterns are interpreted, in conjunction with the existing transportation literature, in relation to public transit, vulnerable road users, and the potential roles of ITS and connected and autonomous vehicles in addressing persistent road-safety disparities.