Response to Rissel and Wen: 'the possible effect on frequency of cycling if mandatory bicycle helmet legislation was repealed in Sydney, Australia: a cross sectional survey'.

They state that people “aged 16-24 years...were significantly more likely to ride more if they did not have to wear a helmet”. This is only found to be true when compared to those aged 55+ but is not shown to be the case compared to the broader adult population. If the intent is to state those aged 16-24 years are significantly more likely than not to cycle more, this is clearly not true as significantly more people responded to the contrary (0.341, 95%CI: 0.235-0.447). Also, significantly more people in the other age groups responded they would not ride more, with an apparent downward trend in proportion by age (see Figure 1).