Using publicly available flight data to analyze health disparities in aeromedical retrieval

Specialist healthcare cannot be provided in all locations. Helicopters can help to reduce the inherent geographical inequity caused by long distances or difficult terrain. However, the selective use of aeromedical retrieval could lead to other forms of health disparities. The aim of this project was to evaluate such inequities in access to helicopter transport.

This was a geospatial analysis of publicly available flight tracking data for 18 emergency medical helicopters in the state of Alabama for a 90-day period between March 2019 and June 2019. Data are presented as the number of incidents attended per population, by population (total, insured, and uninsured), as funnel plots, by county. This method allows the identification of positive and negative outliers.

We identified 672 likely scene retrieval flights. Twelve counties were probable (outside of 99% confidence interval [CI]) high outliers (more helicopter retrievals than expected), and 4 were possible (outside of 95% CI) high outliers. There were 5 possible low outliers (fewer helicopter retrievals than expected) and 6 probable low outliers. Analysis by insurance status revealed similar results. However, there was no easily discernible geographic pattern to this variability.

There is considerable geographical variability in the number of helicopter retrievals, with no easily discernable pattern. Some of this variability may be due to differences in injury epidemiology, but others may be due to case selection. However, the present data are insufficient to come to firm conclusions, and additional study is warranted.