Restricted Medi-Cal Expansion and Healthcare Usage Among Undocumented Farmworkers

To evaluate the impact of California's restricted-scope Medi-Cal program on health insurance coverage and healthcare utilization among undocumented farmworkers.

We use a difference-in-differences approach to compare undocumented farmworkers in California-where restricted-scope Medi-Cal was expanded in 2014-with those in other states that expanded Medicaid under the Affordable Care Act (ACA) but did not implement a similar program for undocumented workers. The analysis exploits nearly a decade of pretreatment data to assess parallel trends.

Restricted-access data from the National Agricultural Workers Survey (NAWS), covering farmworkers in the United States from 2001 to 2020, the last year for which data is available. We identify undocumented farmworkers in the NAWS and extract information on health insurance coverage and healthcare utilization, including use of hospitals/emergency rooms and private clinics.

The results show that following the expansion of restricted scope Medi-Cal, the use of institutional healthcare providers (community health centers, hospitals, and emergency rooms) increased by 8.0 percentage points (95% CI: 0.0044, 0.1564) while the use of private clinics decreased for undocumented farmworkers. This is consistent with an 11.6 percentage points (95% CI: 0.0755, 0.1572) increase in restricted Medi-Cal coverage. We also show that the parallel trend assumption holds, lending support to a causal interpretation.

Our results highlight that restricted Medi-Cal expansion increased access to care.