The Role of Geography in the Assessment of Quality: Evidence from the Medicare Advantage Program.

The Affordable Care Act set in motion a renewed emphasis on quality of care evaluation. However, the evaluation strategies of quality by the Centers for Medicare and Medicaid Services do not consider geography when comparisons are made among plans. Using an overall measure of a plan's quality in the public sector--the Medicare Advantage (MA) star ratings--we explored the impact of geography in these ratings. We identified 2,872 U.S counties in 2010. The geographic factor predicted a larger fraction of the MA ratings' compared to socio-demographic factors which explained less. Also, after the risk adjustments, almost half of the U.S. states changed their ranked position in the star ratings. Further, lower MA star ratings were identified in the Southeastern region. These findings suggest that the geographic component effect on the ratings is not trivial and should be considered in future adjustments of the metric, which may enhance the transparency, accountability, and importantly level the playing field more effectively when comparing quality across health plans.