Seat belt legislation in the Netherlands produced a smaller decrease in fatality rate than expected. This paper investigates why this was so. The initial study compares the driving behaviour of habitual seat belt wearers with those who do not wear seat belts. Non-wearers made two trips along a 10km freeway, one made with the belt on, and one with it off. Habitual wearers always wore their belts. Two additional tasks were also performed after the freeway trips. The first was a double lane change and the second was a braking manoeuvre in front of a fixed obstacle. A follow-up study was carried out in which the original drivers were divided into four groups. One of thesewas given a promise by the experimenter of a considerable incentivefor not having a motor vehicle accident for a year. All subjects returned for a repeat freeway driving test at the end of the year.
Abstract