Impact of bicycle helmet safety legislation on children admitted to a regional pediatric trauma center

Shafi S, Gilbert JC, Loghmanee F, Allen JE, Caty MG, Glick PL, Carden S, Azizhan RG.
J Paediatric Surgery, 1998 Feb;33(2):317-21

BRIEF NOTES
This is not a complete Commentary but a summary of observations and criticisms that have been made relating to this paper

Summary of paper (based on authors' abstract)

208 child bicycle crash victims admitted to the regional pediatric trauma center in Buffalo, NY from 1993 to 1995 were studied retrospectively. Head injuries were classified as concussion alone, skull fractures, intracranial hemorrhages, cerebral contusions or diffuse cerebral edema alone. Only 31 children (15%) wore helmets at the time of the crash. Helmet use rose from 2% to 26% during the period following the enactment of a helmet law on June 1 1994. The proportion of children suffering head injury was similar in both groups. However the type of head injury was different. Helmet wearers were more likely to sustain concussion alone, were less likely to have skull fractures and exhibited a trend toward less intracranial hemorrhages, cerebral contusions and cerebral edema. Excluding the isolated concussions, head injuries were noted in only one helmet wearer and 30 non-wearers. None of the 3 children who died had worn helmets and all died of mulitple head injuries.

General observations

Peer criticism

By Towner et al, 2002 :

Only included children who were admitted to hospital, who were much more likely to have head injury than others.
No protective effect for overall head injury.
Helmeted children showed greater incidence of concussion alone, but numbers very small.
Numbers were very small for some calculations.
This study was difficult to interpret as it suggests that helmets do not protect children from head injuries per se, but only from more severe injuries.
The authors did not attempt to assess the effect of introducing legislation on the pattern of head injuries.

Conclusions

It seems improbable that helmets could protect from serious head injuries but not less serious ones; this also conflicts with reseach that suggests the opposite. The sample size was too small for reliable comparisons.

References

Towner et al, 2002

Towner E, Dowswell T, Burkes M, Dickinson H, Towner J, Hayes M, 2002. Bicycle helmets - a review of their effectiveness: a critical review of the literature. Department for Transport Road Safety Research Report 30.