Reported here are the results of a direct observation survey of safety belt use conducted in March 2001. The purpose of this study is to determine the effect of standard enforcement legislation, implemented in March 2000, on Michigan’s safety belt use rate. In this study, 14,092 occupants travelling in four vehicle types (passenger cars, sport-utility vehicles, vans/minivans, and pickup trucks) were surveyed from March 15 to March 28, 2001. Belt use was estimated for all commercial/noncommercial vehicle types combined (the state-wide safety belt use rate) and separately for each vehicle type. Within and across each vehicle type, belt use by age, sex, road type, day of week, time of day, and seating position were calculated. state-wide belt use was 79.4 percent. When compared with the safety belt use rate determined prior to the implementation of standard enforcement legislation, this survey’s estimated use rate shows that safety belt use in Michigan has increased significantly as a result of the law. However, when compared to the safety belt use rates determined in the surveys conducted immediately following, and three months after the change to standard enforcement, this survey shows that the state-wide safety belt use rate has decreased slightly. In the current survey, belt use was 82.2 percent for passenger cars, 79.4 percent for sport-utility vehicles, 83.3 percent for vans/minivans, and 68.1 percent for pickup trucks. Belt use was higher for females than for males, and higher for drivers than for passengers for all vehicle types combined. Belt use was highest in the 4-to-15 year old age group, followed by the 60-and-over age group, 30-to-59 year old age group, and 16-to-29 year old age group, respectively. Belt use did not vary systematically by time of day or day of week. When results for surveys before and after standard enforcement are compared, the results show that standard enforcement has had its greatest effect on some of the lowest use groups in Michigan: young males and motorists in Wayne County. These analyses show that standard enforcement has been an effective means of increasing safety belt use in Michigan. (Author/publisher)
Abstract