Background A substantial proportion of persons injured in vehicle crashes are passengers. The effect of passengers is not the same for younger and older drivers. There is a negative effect on crash risk for younger drivers and a positive benefit for older drivers.
Methods A population-based study using the West Australian Road Injury Database to compare the crash rates of first year drivers with those driving from more than a year. Crash rates per 10,000 licensed drivers for first year drivers were compared with the rates for drivers with more than one year?s driving experience.
Results Between 1997 and 2000 there were 3589 passengers injured. Male and female passengers were injured equally as often. A passenger was 13 times more likely to be injured if the driver had been licensed for <12 months than with a driver licensed for more than 12 months. Drivers with <12 months driving experience were eight times more likely than drivers with a longer licensing period to be involved in a fatal passenger injury; six times more likely to be involved in a passenger hospitalisation than drivers licensed >12 months. Sixty-three per cent of passengers wore a seat belt, 15% did not (22% unknown). Passengers aged 0 to 16 years and those over 35 years were more likely to wear a seat belt than passengers in other age groups.
Discussion The proportion of injured passengers in this study was similar to that seen in overseas studies before restrictions on carrying passengers were introduced for probationary drivers. The introduction of passenger restrictions in WA needs to be considered or other changes to licensing such as increasing the licensing age.