Fatal crash involvement of unlicensed young drivers: county level differences according to material deprivation and urbanicity in the United States.

OBJECTIVES: This study assessed the association between county level material deprivation and urbanization with fatal road traffic crashes involving young unlicensed drivers in the United States (US).
BACKGROUND: Road traffic crashes have been positively associated with area deprivation and low population density but thus far few studies have been concerned specifically with young drivers, especially those that are unlicensed.
METHODS: A county material deprivation index was derived from the Townsend Material Deprivation Index, with variables extracted from the US Census (2000). An urbanicity scale was adapted from the US Department of Agriculture's Rural-Urban Continuum Codes (2003). Data on fatal crashes involving a young unlicensed driver during a seven-year period (2000-2006; n=3059) were extracted from the Fatality Analysis Reporting System. The effect of deprivation and urbanicity on the odds of the occurrence of at least one fatal crash at the county level was modeled by conditional and unconditional logistic regression.
RESULTS: The conditional model found a positive association between material deprivation and a fatal crash involving a young unlicensed driver (OR=1.19, 95% CI 1.17, 1.21). The interaction between urbanicity and material deprivation was negatively associated in suburban counties for fatal crashes (OR=0.92, 95% CI 0.90, 0.95).
CONCLUSIONS: An association with material deprivation and the likelihood of a fatal crash involving a young unlicensed driver is a new finding. It can be used to inform specific county-level interventions and promote state licensing policies to provide equity in young people's mobility regardless of where they live.