Recent studies do not agree on the possible relationship between medical conditions and traffic safety; most of them do not control for exposure factors. This problem has become more pertinent for scientific studies because of litigation that showed that present regulations about access to driver permits might contravene human rights legislation. In the study, the authors estimate the effect of different medical conditions on truck drivers' distributions of accidents. The data and the models permit simultaneous control for age; medical conditions; exposure factors measured by hours, kilometers, and qualitative factors; and other characteristics of truck drivers. The results show that diabetic truck drivers of the permit class for straight trucks have more accidents than drivers in good health. No other studied medical condition has a significant effect on individual accident distributions. Many risk exposure variables are also significant. The effect of age is discussed in detail. (A)
Abstract