McCarthy M
Department of Community Medicine, University College London.
Public Health. 1991 Jul;105(4):327-34. doi: 10.1016/s0033-3506(05)80218-5.
As a rate per million kilometres travelled, the 'risk' of cycling appears to be high in relation to other forms of transport. Yet, in absolute numbers, there are far fewer cyclist deaths than pedestrian or motor vehicle occupant deaths, and most deaths and serious injuries to pedal cyclists are caused by other road users--principally motor vehicles. The large majority of pedal cyclist deaths are due to head injuries after collision with a motor vehicle. It is therefore commonly proposed that cyclists should wear crash helmets for their own 'safety'. Helmets may protect against fall injuries, but current models are not designed to withstand the impact of collisions with motor vehicles. Evidence for the benefit of pedal cyclists wearing helmets is limited: the existing studies cannot exclude the possibility of different risk-taking behaviour, either by cyclists or by motor vehicle drivers, for helmet wearers compared with non-wearers. A public health policy towards reducing pedal cyclist deaths should seek prevention of accidents, rather than protection from their consequences. Cycling in greater safety would reduce the 'risk' per kilometre travelled, but more cycling might not reduce total cyclist deaths or injuries--because of greater exposure. The 'risk' of cycling--the risk of injury or death--is a complex mix of exposure, 'danger' of the environment, and the perceived risk affecting our precautionary preventive behaviour.
以每行驶一百万公里的比率计算，骑自行车的“风险”相对于其他交通方式似乎较高。然而，从绝对数量来看，骑自行车者死亡的人数远少于行人或机动车乘客死亡的人数，而且大多数骑自行车者的死亡和重伤是由其他道路使用者造成的——主要是机动车。绝大多数骑自行车者的死亡是由于与机动车碰撞后头部受伤。因此，人们普遍建议骑自行车者为了自身“安全”佩戴防撞头盔。头盔可能会防止摔倒受伤，但目前的款式并非设计用于承受与机动车碰撞的冲击力。关于骑自行车者佩戴头盔有益的证据有限：现有的研究无法排除与未佩戴者相比，佩戴头盔的骑自行车者或机动车驾驶员存在不同冒险行为的可能性。一项旨在减少骑自行车者死亡的公共卫生政策应致力于预防事故，而不是防止事故后果。更安全地骑行会降低每公里行程的“风险”，但更多的骑行可能不会减少骑自行车者的总死亡人数或受伤人数——因为骑行暴露增加。骑自行车者的“风险”——受伤或死亡的风险——是暴露、环境“危险”以及影响我们预防行为的感知风险的复杂组合。
