Objective: To investigate the extent to which older drivers pose a risk to other road users, relative to drivers of other ages, using Australian fatal crash data.
Method: The principal data source was the Australian Transport Safety Bureau's National Fatalities Database, which has provided fatality numbers for the most recent available 10-year period (1988, 1990, 1992, 1994, and 1996-2001). For each driver age group ("target drivers"), fatality rates were calculated for the following categories of road users: target driver deaths, their passenger deaths, road users external to the target vehicle but killed in the crash involving the target driver, all road users killed other than target drivers, and all road users killed (including target drivers). Fatality rates were calculated on three bases: per population numbers in each age category, per licensed driver numbers in each age category, and per distance driven for each age category. The different road user fatality rates associated with drivers aged 80 years and older were compared to the rates associated with drivers from younger age categories.
Results: On a per population basis, older drivers had a significantly lower "all road users" fatality rate than all age groups bar one (RR for other age groups: 1.2-3.1) and these differences strengthened once target drivers were excluded (RR: 1.4-5.1), all differences significant. On a per licence basis, older drivers had significantly higher "all road users" fatality rate when compared to the rates for drivers aged 30-39 years through to 70-79 years (RR for these age groups: 0.5-0.7) but once the target drivers were excluded, older drivers' "all other road users & fatality rates for were significantly lower than for drivers aged 17-24 years to 30-39 (RR: 1.3-2.6) years. On a per-distance basis, older drivers had significantly higher all road users fatality rate when compared to the rates for all drivers aged 25-29 years through to 70-79 years (RR for these age groups: 0.1-0.4). Once the target drivers were excluded, older drivers' all other road users fatality rates remained significantly higher than for these other age groups (RR: 0.3-0.7) years.
Conclusions: Based on two of the three bases (per population and per licence), it has been strongly asserted that overall, the older the driver, the less the threat to other road users--and particularly, the less the threat to road users external to the driver's vehicle. Drivers aged 80 years and older appeared to be the greatest threat to other road users only when per distance fatality rates were compared.