The purpose of this paper is to develop a statistical model explaining the relationship between certain driver characteristics and behaviors, crash severity, and injury severity. Applying techniques of categorical data analysis to comprehensive data on crashes in Hawaii during 1990, a structural model relating driver characteristics and behaviors to type of crash and injury severity. The structural model helps to clarify the role of driver characteristics and behaviors in the casual sequence leading to more severe injuries. From the model the effects of various factors in terms of odds multipliers is estimated (that is, how much does each factor increase or decrease the odds of more severe crash types and injuries). It is found that driver behaviors of alcohol or drug use and lack of seat belt use greatly increase the odds of more severe crashes and injuries. Driver errors are found to have a small effect, while personal characteristics of age and sex are generally insignificant. The paper concludes with a discussion of the modeling approach and of the implications of the findings for appropriate traffic safety interventions and future research.
Abstract