Research In Action

A recent study I conducted with colleagues from the Rollins School of Public Health at Emory University, Julia M. Baker, MPH and Carolyn Drews-Botsch, PhD, MPH, demonstrates the power of data in Children’s Hospital of Philadelphia’s electronic health records (EHR) system in helping us continue to examine the rates of driver licensure and risk of crashing among adolescents and young adults with various medical conditions.

The retrospective cohort study, recently published in the Journal of the American Association for Pediatric Ophthalmology and Strabismus, examined the rates of licensure and police-reported crashes for adolescents and young adults with two of the most common types of vision impairment, unilateral vision impairment (UVI) and amblyopia. Both conditions cause reduced vision in one eye and decreased depth perception, both important in driving.

We used ICD-9 codes available in CHOP’s EHR to classify the UVI and amblyopia status of pediatric patients of the CHOP Care Network who were born between 1987 and 1997 and resided in New Jersey. We included only young adults with these impairments whose best-corrected visual acuity was 20/50 or better in at least one eye, which is required to obtain a driver’s license in NJ. We then conducted a unique linkage of these EHR records and NJ driver licensing and crash data to determine the associations between UVI/amblyopia, licensure, and crash involvement.

We found that the young adults with UVI or amblyopia were less likely to get licensed than those with no visual impairment. However, when licensed, neither UVI nor amblyopia was associated with an elevated crash risk as compared to those with no visual impairment. Future studies can help address barriers to licensure for this group and how to enhance driving training to focus on the specific needs of this medical condition.

Value of EHR Data

We are fortunate at CHOP to have the unique ability to retrospectively examine clinical EHR data on a variety of medical conditions. This is due to the strength of a linked EHR system throughout a large healthcare network. Because CHOP began to systemize its EHR data in the early 2000’s, we researchers now have access to a treasure trove of information on all types of medical diagnoses experienced as children by today’s young adult drivers.

We have already examined licensure and crash risk for adolescents with neurodevelopmental differences and visual impairment and look forward to analyzing other medical conditions to help establish the epidemiologic foundation for future translational research. Mobility is an important part of gaining independence as teens with various medical conditions transition to adulthood, and we want to learn how we can best support them whether they drive or not.