Abstract
Purpose :
To identify geographic and socioeconomic variables predictive of residential proximity to retinopathy of prematurity (ROP) clinical trial locations.
Methods :
This was a cross-sectional, retrospective study. Deidentified census-tract level data from public datasets and trial-level data from ClinicalTrials.gov were analyzed. We used an origin-destination cost-matrix to calculate the driving distance and travel time from the population-weighted United States (US) census tract centroid to the nearest clinical trial site. We then used data from the U.S. Census Bureau's American Community Survey and the Centers for Disease Control and Prevention to identify census-tract level socioeconomic factors predictive of driving distance and time. The primary outcomes were time traveled >60 minutes and distance traveled >60 miles from population-weighted census tract centroid to the nearest ROP clinical trial site.
Results :
In a multivariable model, driving time >60 minutes had a significant association with rural vs. urban location [1.19 (1.17-1.22), adjusted odds ratio (aOR) (95% confidence interval), p<0.0001], percentage of population <200% of federal poverty level (FPL) compared to the first quartile [second quartile 1.04 (1.03-1.05), third quartile 1.07 (1.06-1.08), fourth quartile 1.17 (1.16-1.19), p<0.0001], and South [1.06 (1.05-1.07)] and West [1.24 (1.22-1.26), p<0.0001] region as compared to Northeast. Driving time was inversely associated with county-level number of births < 1500g per 1000 people 0.98 (0.98-0.98), p<0.0001. Similar predictors were found in distanced traveled >60 miles.
Conclusions :
Conclusions: There are geographic maldistributions of clinical trial sites for ROP in the United States. Those with higher travel burden are more likely to reside in a census tract that is rural, low-income, and from areas outside the Northeast. Conversely, patients from counties with higher rates of very-low birth weight infants are less likely to live further from clinical trial sites.
This is a 2021 ARVO Annual Meeting abstract.