Motor vehicle crash death rates among passenger vehicle occupants and pedestrians by county-level social vulnerability and urbanicity: the USA, 2019.

Background: Communities experiencing more social vulnerability are disproportionately harmed by environmental disasters, disease, and injury. This cross-sectional study examined whether US county-level vulnerability scores were associated with 2019 passenger vehicle occupant or pedestrian death rates.

Methods: County-level vulnerability was measured by 2020 Centers for Disease Control and Prevention Social Vulnerability Index scores. Scores were based on 16 community-level characteristics categorised into 4 themes: socioeconomic status; household characteristics; race and ethnicity and housing type and transportation. Counties were divided into quartiles from least to most vulnerable, based on the score distribution among all counties. Deaths were identified from the 2019 Fatality Analysis Reporting System. Death rates per 100 000 population were stratified by vulnerability quartile and urbanicity. Large central metropolitan county results used the second least vulnerability quartile as reference.

Results: Among 328 320 065 people across 3140 counties, there were 22 942 occupant and 6272 pedestrian deaths. Occupant death rates were higher in most vulnerable counties compared with least for all urbanicity levels (large central metropolitan: 4.0 vs 2.8; large fringe metropolitan: 7.4 vs 5.2; medium/small metropolitan: 8.9 vs 7.0; non-metropolitan: 18.5 vs 12.2) with disparities prominent in counties experiencing more socioeconomic and household vulnerability. Pedestrian death rates were highest in most vulnerable counties compared with least (large central metropolitan: 2.5 vs 1.4; large fringe metropolitan: 3.3 vs 1.0; medium/small metropolitan: 2.8 vs 0.8; non-metropolitan: 2.4 vs 0.9) with disparities prominent for all four vulnerability types.

Conclusions: Tailoring prevention strategies to communities experiencing infrastructure inadequacies, improving safe transportation options and reducing poverty may help reduce crash death disparities.