In an Indiana University study led by Professor R.F. Borkenstein, drivers involved in accidents in Grand Rapids, Michigan from July, 1962 to June, 1963 were compared with a control group of drivers. Observations were analysed with respect to nine variables, one of which was the blood alcohol level. Accident risk was found to vary significantly higher for drivers with blood alcohol levels of 80mg/100ml and above than for those with blood alcohol levels lower than 10 mg/100ml. Information was also obtained about many aspects of drivers consumption of alcohol. The report comprises a summary of the Borkenstein report and discussion of some of the methods and results. Data concerning drivers with blood alcohol levels of 10-49mg/100ml suggested, generally at a low level of statistical significance, that accident risk rises steadily with alcohol consumption, but at the same time shows more certainly that more frequent drinkers have significantly lower accident risk than non- or infrequent drinkers. If the risk of accident involvement due to alcohol intake is ignored below 80mg/100ml, as a basis for estimating the minimum number of accidents due to alcohol, it is calculated on the basis of the Grand Rapids study that the number of drivers involved in accidents would have been reduced by six per cent. Further analysis of the data is suggested.
Samenvatting