Lee & Mann (Arch Dis Child 2003;88:465–466) make a very poor case for compulsion.
In addition to using a figure for fatalities which is more than double the current rate, they offer no new information on the effectieveness of helmets, preferring to rely on previous data with known weaknesses or meta-analyses which exclude data contra-indicating compulsion.
As a parent and a school governor, I read each new piece of research in the hope that it might answer the following crucial questions, questions to which I have as yet no snwer from these studies or from the Government:
- what evidence is there to support prioritising helmet use above measures to prevent crashes, such as roadcraft training, cycle maintenance initiatives and work on conspicuity
- how is it proposed to mitigate the known, documented deterrent effect of aggressive helmet promotion and compulsion on levels of cycling
- what accounts for the substantial disparity between small-scale studies showing benefit and whole-population and time-series data showing little or no overall benefit
- what justification is there for treating cycling as a special case - greater savings would appear to be indicated from helmet use by pedestrians and motorists
- Is there any evidence that cycle helmet use can be promoted without deterring cycle use;
- Is there any evidence that any protection provided by helmets when head impacts occur is not negated or outweighed due to helmet-wearers facing increased risks of suffering head impacts in the first place;
- Is there any evidence that cycle helmet promotion campaigns can bring about overall reductions in either the rate or severity of cyclists’ casualties;
- Is there any evidence that cycle helmet campaigns are based on a proper assessment of the risk of cycling relative to other activities, the effectiveness of helmets in addressing those risks, and the relative cost-effectiveness of cycle helmet promotion compared with promoting helmet-wearing for pedestrians, vehicle occupants or other groups at risk of head injury, or other interventions to improve cyclist safety.
The authors fail to acknowledge or account for the consistent failure of increased rates of wearing - either voluntary or through compulsion - to yield injury reductions at the population level. As a cyclist, parent and school governor this is of crucial importance to me. I have a pressing need to account for the substantial disparity between the claims of helmet advocates and the evidence from whole population and time-series data.
As usual in pro-helmet articles, they misleadingly claim that case-control studies point to effectiveness. There are, to my knowledge, no true case-control studies on this issue. There are studies which compare communities of helmeted and non-helmeted cyclists, but this assumes that the helmeted and non-helmeted communities are identical in other respects, which clearly they are not - a point eloquently made in rebuttals of Thompson, Rivara and Thompson's 1989 study [Thompson, Rivara & Thompson. New England Journal of Medicine 1989, Vol 320 No 21 p1361-7]. Nor is there any mention of the fact that many cyclists who die of head injuries also have other mortal injuries [The pattern of injury in fatal pedal cycle accidents and the possible benefits of cycle helmets Kennedy A 1996. British Journal of Sports Medicine: 1996 Jun;30(2):130-3]
Their analysis of and approach to the problem of child cyclist injuries is also very disappointing. They rightly identify that "[m]any injuries sustained by children from bicycle accidents arise from loss of attention or poor coordination; others are caused by failure to avoid obstacles such as drains, or undertaking stunts." They do not make clear the proportion of these which are trivial in nature. It is of course always desirable to prevent trivial injuries, but hardly deserving of mandation of protective equipment - especially when there is compelling evidence that such compulsion will deter an activity whose benefits are already known to outweigh its risks.
Further, they do not quantify the proportion of injuries caused through loss of control and stunt riding. If lack of skill causes more injuries than these mechanisms, then logically it makes considerably more sense to address the lack of skill, especially since this will also affect those crashes which do result in injury to other parts of the body than the head.
No attempt is made to put the figures in context. The fatality rate - 22 per year - is, while tragic, small by comparison with either total child fatalities or the number of children who own and use cycles, a figure estimated at around 5 million.
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