The geographic distribution of physician assistants in the US: Clustering analysis and changes from 2001 to 2008

Analysis of the geographic distribution of physician assistants (PAs) across the US explores their practice patterns as well as how and why they changed between 2001 and 2008. Cartographic results suggest that PAs are more clustered across the US than medical doctors (MDs) and that their clusters are larger. In addition, the largest low-PA cluster grew noticeably between 2001 and 2008. Statistical results suggest that PAs did not continue to practice in underserved places in 2008 as they had in 2001. An economic explanation is the most plausible for the latter result, but further analyses with disaggregate data is necessary to generalize such results.