Biological and behavioral factors affecting driving safety.

It can be estimated that human factors concerning the psychophysical condition of the driver are involved in 60-80% of road accidents. Several driver characteristics and driving behaviours due to age, personality traits, diet, alcohol consumption, circadian rhythms, drugs intake and diseases may contribute to a reduced alertness and to unsafe driving behaviours, thus increasing the risk of car crashes. Objective of this article is to highlight the driver characteristics that may contribute to a reduced alertness and/or are correlated to unsafe driving behaviours, thus increasing the risk of car crashes. A better understanding of the human factors affecting motor-vehicle accidents is required to adopt appropriate preventive measure and increase driving safety.