Background The Affordable Care Act (ACA) expanded Medicaid eligibility to improve healthcare access. This study evaluates whether Medicaid expansion led to increased insurance coverage and reduced cost-related barriers to healthcare.

Methods We used Behavioral Risk Factor Surveillance System (BRFSS) data from 2012, 2013, 2015, 2016, and 2018. A Difference-in-Differences (DiD) approach was applied, comparing adults in expansion versus non-expansion states before and after 2014. Logistic regression was employed to calculate odds ratios (OR) along with their corresponding 95% confidence intervals (CI).

Results Medicaid expansion was associated with 25% greater odds of insurance coverage (OR = 1.25; 95% CI: 1.22, 1.28) and 10% lower odds of cost-related barriers to care (OR = 0.90; 95% CI: 0.89 to 0.91, indicating a statistically significant association (p < 0.001).

Conclusion Medicaid expansion under the ACA significantly improved healthcare access by increasing insurance coverage and reducing cost-related barriers.

The authors have declared no competing interest.

The author(s) received no specific funding for this work.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

This study is a secondary analysis of publicly available, de-identified data from the Behavioral Risk Factor Surveillance System (BRFSS), collected by the Centers for Disease Control and Prevention (CDC). The dataset is anonymized and publicly accessible and therefore exempt from institutional review board (IRB) approval. No additional ethical approval was required.

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