Abstract
Previous research examining the relationship between adolescent problem behaviors and young adult traffic outcomes (crashes, convictions, risky driving) has produced differing results. Possible reasons for this may be the heterogeneity of the crash outcomes (from minor fender-benders to fatal crashes), the gender of the driver, and/or the age of the driver. The aim of this research was to investigate the relationship between adolescent problem behaviors and young adult crashes to determine the extent to which the above factors influenced this relationship. This study was part of the Dunedin Multidisciplinary Health and Development Study (DMHDS), which is a longitudinal study of a cohort (n = 1,037) born in Dunedin, New Zealand, from April 1972 to March 1973. This cohort has been followed up regularly since birth, and the data for the present research were obtained at the 18-, 21-, and 26-year-old follow-up interviews. The problem behaviors examined were those identified by Jessor in the theory of problem behavior, namely, tobacco smoking, marijuana use, alcohol use, delinquent behavior, and unsafe sexual behavior. Data for these measures were obtained in personal interviews when the cohort was aged 18 years. The self-reported crash data were obtained at the age 21 and age 26 follow-up interviews. Driving exposure, academic qualifications, employment, being a parent, and marital status were included as potential confounders. The results show that involvement in adolescent problem behaviors predicted crash involvement at age 21 for the females but not the males and at age 26 for the males but not the females. Possible explanations for these differences by age and gender are discussed.