Unveiling Risk Factors in Motorcycle Safety: A Data-Driven Analysis in Spain

Abstract

This study analyses motorcycle safety in Spain using an Exposure-Based Risk Index (IREx) methodology applied to 4,006,804 registered motorcycles and 30,875 road accidents from 2022. The research integrates regionally specific Vehicle Kilometers Travelled (VKT) estimation combining traffic census data, technical inspection information, and statistical modelling. Key findings reveal rider age as the predominant risk factor, with riders ≤24 years showing higher accident probability. Vehicles with high-displacement engines (>500cc) and Sport touring motorcycles present elevated mortality risks compared to other motorcycle categories. The methodology addresses critical gaps in exposure-based assessment through comprehensive Spanish traffic pattern analysis and refined risk stratification with transparent uncertainty quantification. Findings support ASEAN NCAP's motorcycle safety protocol development by establishing evidence-based risk profiles and providing actionable insights for targeted interventions, particularly for high-risk populations. This scalable framework offers an adaptable motorcycle risk assessment methodology for diverse regional contexts, supporting evidence-based road safety policies.