Cell phone use while driving laws and motor vehicle driver fatalities: differences in population subgroups and location.

PURPOSE: Research suggests that cell phone use while driving laws are associated with lower driver fatalities. This study seeks to determine whether this relationship is modified by driver age (16-24, 25-39, 40-59, ≥60), sex (male, female), race/ethnicity (white non-Hispanic, white Hispanic, black non-Hispanic, other), or rurality (rural, urban).

METHODS: Fatality Analysis Reporting System data were merged with state legislation (2000-2014). The exposure was the type of legislation in effect. The outcome was non-alcohol-related driver fatalities by state-quarter-year. Incident rate ratios were estimated using generalized Poisson mixed regression for overdispersed count data with robust standard errors.

RESULTS: Amongst 190,544 drivers, compared to periods without bans, universal hand-held calling bans were associated with 10% (adjusted incident rate ratio = 0.90, 95% confidence interval 0.84, 0.96) lower non-alcohol-related driver fatalities overall and up to 13% lower fatalities across all age groups and sexes but not for race/ethnicity or rurality. When comparing state-quarter-years with bans to those without, universal texting bans were not associated with lower fatalities overall or for any demographic group.

CONCLUSIONS: The relationships between cell phone laws and non-alcohol-related driver fatalities are modified by driver demographics, particularly for universal hand-held bans. Universal hand-held calling bans may benefit more types of drivers compared to texting bans.