Background: Following the Affordable Care Act's Medicaid expansions, access to care improved through elevated coverage rates among the low-income population. In Michigan, a major factor contributing to improved access among low-income patients was increased Medicaid acceptance in primary care settings.
Objectives: Prior evidence shows substantial geographic variation preacceptance and postacceptance of Medicaid. In this study, we determine whether physician's willingness to accept new Medicaid patients is moderated by the availability of other providers in close proximity.
Methods: The study uses Michigan simulated patient (ie, "secret shopper") data collected during 2014 and 2015, and applies a difference-in-differences styled event-study regression approach comparing trends in Medicaid acceptability and appointment scheduling between areas in Michigan with higher densities of primary care providers against those with lower densities of providers that could arguably be classified a health professional shortage areas.
Results: Through one year after Michigan's Medicaid expansion, practices in low-supply areas appeared no more likely (P>0.10) to turn away a newly insured Medicaid patient than a practice in a supply-rich area. The wait times for patients in a low-supply area were about a day longer (P<0.05) than for patients in supply-rich areas through 4 months after the expansion, though this difference dissipated through 8 and 12 months after the expansion.
Conclusions: These results indicate that newly insured Medicaid patients are gaining access to care in settings with limited health care supply.