Some studies suggest that the benefits of antilock brake systems (ABS) may be offset through behavioral adaptation, such as driving faster or following closer. Whether preconditions for behavioral adaptation exist was examined by investigating driver knowledge and beliefs about ABS. Telephone interviews were conducted throughout Quebec early in 1999 with principal drivers of a stratified random sample of 404 drivers with currently registered light-duty vehicles, registered to the same person for at least 18 months. The response rate was 82 percent of 492 reached. Only medium-range and high-end 1990-1995 vehicles, for which ABS was either standard equipment or unavailable, were selected. The protocol involved mostly open questions that encouraged respondents to reveal their knowledge and beliefs with minimal prompting. The results indicated an important lack of understanding, on the part of a majority of drivers, regarding the functioning and use of ABS. This varied from an inability to identify conditions in which ABS is favorable or unfavorable to serious misconceptions; about 25 percent were wrong about whether their vehicle was ABS equipped. Cognitive preconditions for behavioral adaptations—sometimes increased prudence—were found for a minority of this sample, and there may be a relationship between a low level of knowledge and the perceived possibility of driving faster with these brakes. There appears to be a case for improved public and dealer-delivered information on the advantages and disadvantages of ABS in different driving conditions, which if balanced should not increase unsafe behavioral adaptation.
