Volume 53 | Number S1 | August 2018

Abstract List

Michael R. Daly M.Com., Jennifer M. Mellor Ph.D., Marco Millones Ph.D.


To investigate the association between older adults’ potentially avoidable hospitalization rates and both a geographic measure of primary care physician () access and a standard bounded‐area measure of access.

Data Sources

State physician licensure data from the Virginia Board of Medicine. Patient‐level hospital discharge data from Virginia Health Information. Area‐level data from the American Community Survey and the Area Health Resources Files. Virginia Information Technologies Agency road network data. Census Bureau /Line boundary files.

Study Design

We use enhanced two‐step floating catchment area methods to calculate geographic accessibility for each Code Tabulation Area in Virginia. We use spatial regression techniques to model potentially avoidable hospitalization rates.

Data Collection/Extraction

Geographic accessibility was calculated using Arc. Physician locations were geocoded using GeoServices and Arc.

Principal Findings

Increased geographic access to s is associated with lower rates of potentially avoidable hospitalization among older adults. This association is robust, allowing for spatial spillovers in spatial lag models.


Compared to bounded‐area density measures, unbounded geographic accessibility measures provide more robust evidence that avoidable hospitalization rates are lower in areas with more s per person. Results from our spatial lag models reveal the presence of positive spatial spillovers.