Epidemiology in action: The case of the bike helmet

When I was first introduced to the Oxford biking community, I was surprised to see a large amount of helmeted cyclists. As a Dutch person, I did not wear a helmet purely out of principle, and this was viewed upon as risk-prone behaviour by my fellow classmates. It even went so far as that Professor Robyn Norton, who came to lecture us one day on injuries as causes of death, compared not wearing a helmet with smoking. She argued that the scientific evidence linking the prevention of head injuries to wearing a helmet is equally strong as the evidence linking smoking to lung cancer (see this meta-analysis).

I could not let this accusation pass me by completely, so I (partially successfully) argued that there’s the risk compensation theory – where by the behaviour of the cyclist changes when they wear a helmet, offsetting its protective benefits. The benefit of a helmet also depends on the environment the cyclists finds him or herself in.  If this environment prevents most of cycle traffic accidents from happening, surely a helmet would not confer a substantial decrease in absolute protection. She agreed with me on this, but immediately pointed out that the cycle infrastructure in Oxford is very different from that in the Netherlands. And there she had a point.

Because, despite what Charlie Foster so enthusiastically told us about Oxford as a cycle-friendly city, it leaves a lot to be desired from the (maybe spoiled) Dutch point of view. Sharing your cycle lane with buses or pedestrians was not something I had previously encountered. Neither was I used to cycling inches from cars on roads without a cycle lane. I was also surprised by the relatively unfriendly attitude towards cyclists. In the Netherlands, cyclists rule the road. Here, I have to be constantly careful not to be overrun by cabs or double-decker buses.

The quality of the road and the fact that Oxford has hills were also things I had to get used to. The daily descent of the Headington Hill is a returning pain, and I learned to keep my eyes on the road on all times lest I unknowingly found myself hitting a hole in the asphalt and almost falling off my bike.

The question of the helmet was decided for me when one of my classmates had a cycling accident when an inattentive driver suddenly opened his car door on him. His helmet saved him from serious injury. Epidemiology in action, as he liked to call it.

I could no longer ignore the evidence. I’ve worn a helmet ever since.

Sophie Bots is currently doing an MSc in Global Health Science at NDPH. Before she came to study in Oxford, she studied medical sciences in Utrecht, The Netherlands and did an internship at the George Institute, Oxford.