Background Children ages 5–14 years have the highest rate of bicycle-related injuries in the country. However, helmet use among US children remains low. This paper compares children's helmet use to that estimated from an earlier study, and explores regional differences by existing helmet legislation.

Methods Telephone interviews were completed by 9684 respondents. The subset with at least one child in the household (2409 respondents) answered questions about their bicycle helmet use.

Results Almost half (48%) of the children always wore their helmet, 23% (373) sometimes wore their helmet, and 29% (477) never wore their helmet. Helmet wearing was significantly associated with race, ethnicity and child age (p values <0.01) but was not associated with the sex of the child. Other significant predictors (p values <0.01) of helmet use included household income, household education, census region and bicycle helmet law status. State-wide laws were more effective than laws covering smaller areas. The proportion of children who always wore a helmet increased from 25% in 1994 to 48.2% in 2001–2002. Significant increases in use from 20% to 26% were seen among both sexes, younger and older children, and in all four regions of the country.

Conclusions While there has been substantial progress in the number of children who always wear their bicycle helmets, more than half do not. The task at hand is to maximise the use of helmets by taking full advantage of methods that promote consistent helmet use.