Due to small cell sizes, for subsequent cross tabulations, helmet use was dichotomised as either always or not always including nearly always, sometimes, seldom or rarely, and never. Frequency distributions of ATV riding were calculated for riders overall and by gender, geographic region and MSA status. Frequency distributions of helmet use were calculated for riders overall and by gender, MSA status and riding frequency. The standard four US Census regions west, south, northeast and midwest were used. All analyses were conducted using SAS V. 9. 3 SAS Institute Inc, Cary, North Carolina, USA. Standard Wald CIs for proportions were produced using the ‘surveyfreq’ procedure. Differences between proportions were considered statistically significant if the 95% CIs did not overlap. A total of the 833 YouthStyles respondents provided information about ATV riding. After sampling weights were applied, the data set contained 831 observations.

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