Head injuries as a cause of road travel death in cyclists, pedestrians and drivers

Despite the well-recognised benefit for individuals and communities of increased active travel, cycling remains a minority travel mode in many high income countries. Fear of injury is often cited as a reason. Campaigns to promote cycle helmet wear may contribute to this. However, there is little information on the importance of head injuries to cyclists and other road users as a cause of death for road travel fatalities.
Using national mortality statistics, the authors identified fatalities in England 2007–2012 among: pedestrians who were walking for travel (whether they were hit by a vehicle or fell); cyclists who were travelling; and drivers of cars or vans. We examined 'secondary causes' of death for those road travel fatalities, comparing travel modes and grouped causes of death (from national mortality statistics) as numbers and as rates. For rates, we used as denominators distance travelled and time spent travelling by mode, age, and sex from National Travel Surveys for the same six years.
Head injury was the secondary cause of death for 269 cyclists, 1324 pedestrians and 1046 drivers, accounting for 46%, 42% and 25% of road travel deaths at all ages in each mode respectively. Head injury was the commonest cause of death in cyclists, but most pedestrian and driver deaths were from multiple injuries. Rates of fatal head injury per bnkm in males aged 17+ for cycling, walking, and driving were 11.2 (95% CI 9.7–12.9), 23.4 (21.8–25.0) and 0.7 (0.6–0.7) respectively. Female fatality rates were 8.8 (6.2–12.0), 9.6 (8.7–10.7) and 0.4 (0.3–0.4) per bnkm respectively. Using time as the denominator, rates were 0.16 (0.14–0.19),0.10 (0.10–0.11) and 0.03 (0.028–0.032) respectively in men and 0.10 (0.07–0.14), 0.04 (0.037–0.045), and 0.01 (0.012–0.016) respectively in women, per million hours travelled.
The study concludes that head injuries in cyclists are often considered to be an important cause of road travel death, but this depends on the metric used for assessing importance. Pedestrians and drivers account for five and four times the number of fatal head injuries as cyclists. No-one is calling for pedestrians to wear helmets although the fatal head injury rates are similar for cyclists and pedestrians. The rate is higher for cyclists than pedestrians by time travelled and is higher for pedestrians than cyclists using distance travelled.