In defence of the 'low-mileage bias'.
There has been a long-recognised association between extent of driving and crash involvement: the lower the annual mileage driven, the higher the per-distance crash rate. Because older drivers generally drive less distance per year than others, this association has been used to explain much of their apparent over-involvement in crashes. Several studies from different countries around the world have demonstrated this 'low-mileage bias' and the relative safety of older drivers. However all studies have relied upon self-reported crash involvement and driving activity. Staplin et al. [Staplin, L., Gish, K., Joyce, J., 2008. 'Low mileage bias' and related policy implications-a cautionary note. Accident Analysis and Prevention 40, 1249-1252] have drawn attention to the discrepancy between self-reported and odometer-based driving distances and have argued against the credibility of the low-mileage bias. This paper has re-worked initial data from an early study which supported low-mileage bias, this time using odometer-based readings rather than self-reported mileage. Accepting the odometer readings at face value, the low-mileage bias remains evident, albeit at a reduced level.
Langford
Jim
J
Monash University Accident Research Centre, Building 70, Monash University, Clayton, Vic. 3800, Australia. jim.langford@muarc.monash.edu.au
Koppel
Sjaanie
S
McCarthy
Dennis
D
Srinivasan
Sivaramakrishnan
S
D000063:Accidents, Traffic / Q000706:statistics & numerical data*; D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001334:Automobile Driving / Q000706:statistics & numerical data*; D015982:Bias; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D014481:United States / Q000453:epidemiology; D055815:Young Adult