Avoiding road traffic injuries: 25 years of providing evidence on road safety at the city level

Abstract Description of the problem Barcelona, a dense Mediterranean city with high mobility and many motorcyclists, established a road traffic injury surveillance system in the early 1990s, integrating police, hospital, and forensic data. From 2000 to 2023, ten interventions were evaluated, including legislative measures (helmet law, motorcycle license, penalty point system) and infrastructure changes (speed cameras, 30 km/h zones, safe school routes, advanced stop lines for motorcycles, red-light cameras). Most evaluations used quasi-experimental designs with comparison groups. This study assessed the effectiveness of these policies in preventing injuries by transport mode, gender, and injury severity between January 2008-when most interventions were in place-and December 2023. A pre-post time series analysis modelled observed vs. expected injuries, adjusting for trends, seasonality, the economic crisis, and COVID-19. Results Between 2008 and 2023, over 34,800 road traffic injuries were prevented, including nearly 1,000 severe injuries. By mode, 4,700 pedestrian, 12,300 car occupant, and 3,200 moped injuries were avoided, while 5,200 more injuries than expected occurred among motorcyclists, partly due to relaxed licensing laws. Speed cameras reduced injury collisions by 27-30%; 30 km/h zones reduced total injuries by 12.2% and motorcyclist injuries by 28.2%; safe school routes cut child injuries by 36.6% and child pedestrian injuries by 39.9%. Some measures, such as advanced stop lines for motorcycles and red-light cameras, had limited or adverse effects. Lessons A public health approach with strong surveillance and systematic evaluation is essential for urban road safety. Not all interventions are equally effective; local adaptation and continuous monitoring are key. Quantifying prevented injuries underscores the value of evidence-based, intersectoral policies integrating health, mobility, and enforcement to improve population health. Key messages • Over 34,800 road traffic injuries were prevented in Barcelona (2008–2023) thanks to mobility interventions. • Ongoing evaluation and intersectoral collaboration are crucial to adapt strategies effectively.