Vehicle safety characteristics in vulnerable driver populations

Abstract

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.

Keywords:

• Automobile driving
• young drivers
• teen drivers
• older drivers
• traffic accidents
• vehicle safety

Acknowledgments

The authors would like to thank Christina Labows, BA and Melissa Pfeiffer, MPH for their assistance in preparing this manuscript and Jalaj Maheshwari, MS for his help extracting data from the vPIC platform and thoughtful suggestions. We also thank the NJ Department of Transportation, NJ Motor Vehicle Commission, and NJ Office of Information Technology for their assistance in providing data. This work was supported by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Award Numbers R21HD092850 and R21HD098276 (PI: Curry). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. The sponsor had no role in the: design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; or decision to submit the manuscript for publication. Drs. Curry and Metzger had full access to all of the data in the study and take responsibility for the integrity of the data and accuracy of data analysis. None of the authors have a conflict of interest or financial disclosure to report.

Data availability statement

The data that support the findings of this study are available from the NJ Motor Vehicle Commission and Department of Transportation. Restrictions apply to the availability of these data, which were used under a Memorandum of Agreement for this study. New Jersey crash data are available at https://www.state.nj.us/transportation/refdata/accident/.