The number of vehicles is about 3 million. The drug problems are considered to be rather below than above the European mean. Our finding that a psychoactive drug other than alcohol is involved in every third case under suspicion of influenced driving in this country comes from a non-selected, nationwide material. It can therefore probably to some extent be considered to be representative for other nations also. Differences in the awareness by the police of this problem, different legislation and other factors may contribute to variations between countries with regard to the real prevalence of the problem as well as to its discovery.
Some generalizations appear, however, to be possible to make.
The focus on alcohol should not mislead us to forget other drugs that could be present very often in suspected influenced driving cases. Thus a negative or low breath-alcohol test should not be used as the only measure to free a person from further investigation in suspected driving cases. Accordingly, the look for better tests to discover influenced driving due to other drugs than alcohol should be intensified. On the road detection of intoxicated drivers and screening for drugs in these offenders. J. of Forensic Sci.