Access to Primary, Mental Health, and Specialty Care: a Comparison of Medicaid and Commercially Insured Populations in Oregon.

OBJECTIVE: To describe how access to primary and specialty care differs for Medicaid patients relative to commercially insured patients, and how these differences vary across rural and urban counties, using comprehensive claims data from Oregon.
DESIGN: Cross-sectional study of risk-adjusted access rates for two types of primary care providers (physicians; nurse practitioners (NPs) and physician assistants (PAs)); four types of mental health providers (psychiatrists, psychologists, advanced practice NPs or PAs specializing in mental health care, behavioral specialists); and four physician specialties (obstetrics and gynecology, general surgery, gastroenterology, dermatology). PARTICIPANTS: 420,947 Medicaid and 638,980 commercially insured adults in Oregon, October 2014-September 2015. OUTCOME: Presence of any visit with each provider type, risk-adjusted for sex, age, and health conditions.
RESULTS: Relative to commercially insured individuals, Medicaid enrollees had lower rates of access to primary care physicians (- 11.82%; CI - 12.01 to - 11.63%) and to some specialists (e.g., obstetrics and gynecology, dermatology), but had equivalent or higher rates of access to NPs and PAs providing primary care (4.33%; CI 4.15 to 4.52%) and a variety of mental health providers (including psychiatrists, NPs and PAs, and other behavioral specialists). Across all providers, the largest gaps in Medicaid-commercial access rates were observed in rural counties. The Medicaid-commercial patient mix was evenly distributed across primary care physicians, suggesting that access for Medicaid patients was not limited to a small subset of primary care providers.
CONCLUSIONS: This cross-sectional study found lower rates of access to primary care physicians for Medicaid enrollees, but Medicaid-commercial differences in access rates were not present across all provider types and displayed substantial variability across counties. Policies that address rural-urban differences as well as Medicaid-commercial differences-such as expansions of telemedicine or changes in the workforce mix-may have the largest impact on improving access to care across a wide range of populations.