Decline in Australian head injuries linked to helmet law

UNSW study says intervention helped halve serious injuries in 2010 alone

The report by researchers at UNSW will only add fuel to the compulsory helmet fire

The number of serious cyclist head injuries in New South Wales, Australia has been reduced by around a half over the past two decades through the combined effect of compulsory helmet laws and improved cycling infrastructure, a study has found.


The research, led by Dr Jake Olivier from the University of New South Wales and published in the Accident Analysis and Prevention journal, also found that despite a rapid growth in cycling’s popularity, head injuries serious enough to require hospital admission are declining at a rate of 4% a year.

His team looked at data from when the mandatory helmet laws were introduced in the state in 1991 through to 2010. They also looked at hospital admissions for serious arm injuries to help distinguish head-injury trends from broader bike accident rates.

Between 1991 and 2010, arm injuries rose by 145% (660 to 1620 per year) while head injuries increased by just 20% (590 to 706). The report also has a couple of data points from 1990, a year before the helmet law was introduced, which show that arm injuries were then lower than head injuries, with the latter being 900.

This should be viewed in the context of a population increase (5.9m, 1991 to 7.2m, 2010) and an increase in people riding bikes (a survey by the Australian Sports Commission in 2010 showed participation increased from 400k (2000) to 604k (2010). The degree to which cycling participation levels dropped between 1990 and 1991 as a result of the mandatory helmet law is unclear, however.

“We found that the overall benefit of mandatory helmet legislation in lowering head injuries was larger than previously reported and has been maintained over the past two decades,” said Dr Olivier. “Before the law commenced in 1991, bicycle-related head injury rates exceeded those of arm injuries. By 2006 [when cycling infrastructure was improved in the state), head injuries were 46% lower than arm injuries.

“Significantly, we also found that bicycle-related head injuries have steadily declined even further since 2006 (51% in 2010), when serious spending on cycling infrastructure began” [the report cites $AUD29.3m spent by the NSW state government on bicycle facilities in 2008/09 including 53km of on-road cycle paths and 44km off-road].

“This decline is happening despite the State’s population rising by 22% during the study period and despite cycling participation rates rising by 51% in the past decade.

“So there’s no room for doubt that hundreds of serious head injuries are now being avoided every year thanks to helmets, bike lanes and segregated cycleways.

“Assuming head injury rates had increased at the same rate as arm injuries, 1,446 NSW cyclists would have been hospitalised in 2010 with serious head injuries without these interventions, whereas the actual number was only 706. In other words, compulsory helmets and cycling infrastructure prevented 740 serious head injuries in that year alone.”

Professor Raphael Grzebieta, Chair of Road Safety at the UNSW Transport and Road Safety Research (TARS) group – who, along with Scott Walter, is a co-author of the study – says the results show that calls for the removal of cycling infrastructure and the repeal of mandatory helmet legislation relating to cyclist safety are both unfounded.

“The Safe-System Approach adopted by all state and federal ministers in their national road safety strategy – involving multiple safety interventions – delivers significantly greater safety benefits than individual interventions alone. The study shows that cycling infrastructure doesn’t simply get more people cycling, it makes it much safer for them to do so when combined with wearing a helmet.”


To read the full report, click here.