​Summary: This study evaluates variation in the availability of primary care new patient appointments for Medi-Cal (California's Medicaid) enrollees in Northern California, and its relationship to emergency department (ED) use after Medicaid expansion. Authors placed simulated calls by purported Medi-Cal enrollees to 581 primary care clinicians (PCCs) listed as accepting new patients in online directories of Medi-Cal managed care plans. Data from the California Health Interview Survey (CHIS), Medi-Cal enrollment reports, and California hospital discharge records were used in analyses. Authors developed multilevel, mixed-effect models to evaluate variation in appointment access. Multiple linear regression was used to examine the relationship between primary care access and ED use by county.

Findings: Availability of PCC new patient appointments to Medi-Cal enrollees lacking a PCC varied significantly across counties in the multilevel model, ranging from 77 enrollees to 472 enrollees per each available new patient appointment. Just 19% of PCCs had available appointments within the state-mandated 10 business days. Clinicians at Federally Qualified Health Centers had higher availability of new patient. Counties with poorer PCC access had higher ED use by Medi-Cal enrollees.

In contrast to findings from other states, access to primary care in Northern California was limited for new patient Medi-Cal enrollees and varied across counties, despite standard statewide reimbursement rates. Counties with more limited access to primary care new patient appointments had higher ED use by Medi-Cal enrollees.

This study cites 2015 California Health Interview Survey (CHIS) data.