Australian Health Promotion Association

Chris Rissel and Li Ming Wen

Introduction: Cycling as a form of regular physical activity that is accessible to people of all ages confers substantial health benefits.1-4 Increasingly in Australia, there are calls to increase levels of cycling because of the multiple co-benefits that come from a shift from private motor vehicles to bicycles, including reduced dependence on potentially dwindling oil supplies, less air and noise pollution, less greenhouse gas emissions, less congestion plus health benefits.5-8

The Australian National Cycling Strategy has a goal to double the number of people cycling by 2016.9 New South Wales, the most populous Australian state, in its State Plan has set a target to increase the mode share of bicycle trips made in the Greater Sydney region, at a local and district level, to 5% by 2016,10 and has published a BikePlan which outlines how this target can be achieved.11 Individual local government areas have also set targets, such as the City of Sydney’s Cycle Strategy and Action Plan 2007-2017, which has a target of 10% of trips to be made by bike by 2016.12 In 2007, 1.2% of trips in the Sydney metropolitan area were made by bike.13

It is generally understood what needs to be done to increase cycling levels. Better urban design such as better cycling infrastructure, higher density development, mixing residential and commercial land use, and shorter trip distances will facilitate more cycling.14 Other strategies to encourage cycling include behaviour change programs such as TravelSmart, Ride to Work and Ride to School programs, public bicycle events to encourage infrequent and novice riders to cycle in a supportive social environment, and bicycle education programs for both children and adults.14

One issue that is not usually discussed when considering cycling promotion strategies in Australia is that of mandatory bicycle helmet legislation. This legislation remains controversial,15,16 and represents differing public health perspectives (injury prevention versus physical activity promotion)17,18 as well as disagreements about the evidence of the effectiveness of the legislation19-21 and civil liberties.22

Advocates for helmet laws cite evidence from bio-mechanical tests and case-control studies, including Cochrane Reviews of the case control studies,23 that repeatedly show that helmets protect against impact to the head15,18 if worn correctly.24 However, a recent review found that some of these studies were influenced by publication bias and time-trend bias that was not controlled for and, as a result, produced inflated estimates of the effectiveness of bicycle helmets.16 Opponents of helmet laws claim that mandatory helmet legislation has reduced the number of people cycling and this is the main cause of any reductions in cycling-related injuries attributed to the legislation. The reduction in numbers of people cycling may have actually increased the risk to the remaining cyclists because of Smeed’s Law and reduced safety in numbers, and also because of risk compensation.25,26 One UK study found that motor vehicle drivers leave significantly less room when overtaking a helmeted cyclist.27 Another found that cyclists accustomed to wearing helmets ride significantly faster (and presumably take more risks) when wearing helmets than without.28 Further, they argue that the debate over what impact protection helmets may provide is a distraction from the main bicycle-related health issue: the safety of the bicycling environment, and that cost-benefit analyses do not support mandatory helmet use.29,30

The introduction of mandatory bicycle helmet legislation in Australia in 1991 was reported to have led to a 25-38% reduction in people cycling in Western Australia,31 a reduction of 47% of NSW students riding to school (much higher for females),32 and 29% fewer adult and 42% fewer child cyclists (36% overall) in Melbourne.33 This negative effect on cycling levels was also observed in New Zealand when bicycle helmet legislation was introduced in 1994, with a 51% drop in the number of trips by bicycle between 1989-1990 and 2003-2006.34 However, a Canadian study found no change in self-reported bicycle use in two provinces that introduced helmet laws, but failed to report the effect of legislation on helmet use in those provinces.35

There are no Australian data on stated preference for bicycle helmet wearing. This study seeks to examine if, 20 years after the introduction of helmet legislation in Australia, people in Sydney say they would cycle more if helmets were not required, how often they would wear helmets, and to describe the characteristics of these people.

Issue addressed: Australia has national, state and city targets to increase levels of cycling. The possible effect of repealing mandatory bicycle helmet legislation on the frequency of cycling in Sydney is examined.
Methods: A cross sectional survey by a market research company was conducted, using quota sampling, in Sydney, Australia. Participants were 600 residents aged 16 years and older. Data were collected in October 2010 using computer-assisted telephone interviews from randomly sampled households, with one respondent per household. The primary outcome measures were propensity to cycle more if a helmet was not required, how often a respondent who cycled would cycle without a helmet, and opinion on compulsory wearing of bicycle helmets. Frequency of cycling, and demographic questions were also assessed. Multiple logistic regression models were run for each of the three main outcomes.
Results: One in five (22.6%, 95% CI 18.8-26.4%) respondents said they would cycle more if they did not have to wear a helmet, particularly occasional cyclists (40.4% of those who had cycled in the past week and 33.1% of those who had cycled in the past month). Almost half (47.6%) of respondents said they would never ride without a helmet, 14.4% said ‘all the time’, 30.4% said ‘some of the time’ and the rest were not sure. One third (32.7%, 95% CI 28.5-37.0%) of respondents did not support mandatory helmet legislation.
Conclusions: While a hypothetical situation, if only half of the 22.6% of respondents who said they would cycle more if they did not have to wear a helmet did ride more, Sydney targets for increasing cycling would be achieved by repealing mandatory bicycle helmet legislation. A significant proportion of the population would continue to wear helmets even if they were not required to do so.
So what? To the extent that Sydney is representative of the rest of Australia, the repeal of mandatory helmet legislation would be likely to substantially increase cycling in Australia.

Health Promotion Journal of Australia 2011; 22: 178-83