Do Avoidable Hospitalization Rates among Older Adults Differ by Geographic Access to Primary Care Physicians?
Published online on June 28, 2017
Abstract
Objective
To investigate the association between older adults’ potentially avoidable hospitalization rates and both a geographic measure of primary care physician (PCP) access and a standard bounded‐area measure of PCP 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. US Census Bureau TIGER/Line boundary files.
Study Design
We use enhanced two‐step floating catchment area methods to calculate geographic PCP accessibility for each ZIP Code Tabulation Area in Virginia. We use spatial regression techniques to model potentially avoidable hospitalization rates.
Data Collection/Extraction
Geographic accessibility was calculated using ArcGIS. Physician locations were geocoded using TAMU GeoServices and ArcGIS.
Principal Findings
Increased geographic access to PCPs is associated with lower rates of potentially avoidable hospitalization among older adults. This association is robust, allowing for spatial spillovers in spatial lag models.
Conclusions
Compared to bounded‐area density measures, unbounded geographic accessibility measures provide more robust evidence that avoidable hospitalization rates are lower in areas with more PCPs per person. Results from our spatial lag models reveal the presence of positive spatial spillovers.