The role of the drinking driver in traffic accidents (the Grand Rapids study)

Abstract

Blood alcohol concentrations (BACs) over 0.04% are definitely associated with an increased accident rate. The probability of accident involvement increases rapidly at BACs over 0.08%, and becomes extremely high at BACs above 0.15%. When drivers with BACs over 0.08% have accidents, they tend to have more single vehicle accidents, more severe (in terms of injury and damage) accidents and more expensive accidents than sober drivers. BACs of 0.04% and below apparently are not inconsistent with traffic safety. Many factors other than alcohol are related to the probability of accident involvement. The driver classes with the worst accident experience, in addition to the alcoholically impaired, are the young or very old, the inexperienced and those with less formal education. Persons with the most education, those with better jobs and the middle aged, have better than average accident experience. The effects of alcohol are consistent within the various socioeconomic classes considered. High BACs are always associated with bad accident experience. At the higher BACs, the difference in the accident potential between the various classes of drivers is unimportant. An important aspect of the applied survey technique is that it is adaptable to assessing the effect of various policies directed at the drinking driver. Drinking and driving is clearly associated with the frequent use, or abuse, of alcohol. Many drivers with BACs overestimate the number of drinks that it is safe to have before driving. The tendency to drive after drinking is related significantly to the socioeconomic categories appearing most frequently in the drinking driver class.