Vehicle safety characteristics in vulnerable driver populations.

OBJECTIVE

National data suggest drivers who are younger, older, and have lower socioeconomic status (SES) have heightened crash-related injury rates. Ensuring vulnerable drivers are in the safest vehicles they can afford is a promising approach to reducing crash injuries in these groups. However, we do not know the extent to which these drivers are disproportionately driving less safe vehicles. Our objective was to obtain population-based estimates of the prevalence of important vehicle safety criteria among a statewide population of drivers.

METHODS

We analyzed data from the NJ Safety and Health Outcomes warehouse, which includes all licensing and crash data from 2010-2017. We borrowed the quasi-induced exposure method's fundamental assumption-that non-responsible drivers in clean (i.e., only one responsible driver) multi-vehicle crashes are reasonably representative of drivers on the road-to estimate statewide prevalence of drivers' vehicle characteristics across four driver age groups (17-20; 21-24; 25-64, and ≥65) and quintiles of census tract median household income (n = 983,372). We used NHTSA's Product Information Catalog and Vehicle Listing platform (vPIC) to decode the VIN of each crash-involved vehicle to obtain model year, presence of electronic stability control (ESC), vehicle type, engine horsepower, and presence of front, side, and curtain air bags.

RESULTS

The youngest and oldest drivers were more likely than middle-aged drivers to drive vehicles that were older, did not have ESC, and were not equipped with side airbags. Additionally, across all age groups drivers of higher SES were in newer and safer vehicles compared with those of lower SES. For example, young drivers living in lowest-income census tracts drove vehicles that were on average almost twice as old as young drivers living in highest-income tracts (median [IQR]: 11 years [6-14] vs. 6 years [3-11]).

CONCLUSIONS

Vehicle safety is an important component of seminal road safety philosophies that aim to reduce crash fatalities. However, driver groups that are overrepresented in fatal crashes-young drivers, older drivers, and those of lower SES-are also driving the less safe vehicles. Ensuring drivers are in the safest car they can afford should be further explored as an approach to reduce crash-related injuries among vulnerable populations.