The evidence that they reduce head injuries is too strong to ignore

Papers p 1055

Bicycling is a worldwide activity. In both developed and developing countries it serves as an important means of transportation as well as an enjoyable recreational activity for adults and children. Thus, injuries related to bicycling are comparatively common, and head injuries account for one third of visits to emergency departments, up to two thirds of hospitalisations, and three quarters of deaths.1 Head injuries also carry a substantial risk of long term disability. Thus, preventing head injuries associated with this common, worldwide activity is important.

Safety helmets for bicycling have been available for at least 20 years. Although randomised controlled trials have become the gold standard for providing evidence of the effectiveness of clinical interventions, these trials are not feasible for examining whether helmets prevent head injuries. Given that the rate of head injury is about 20 injuries per 100 000 people, a randomised controlled trial would need to involve tens …