Factors influencing primary care providers' decisions to accept new Medicaid patients under Michigan's Medicaid expansion.

Objectives: Michigan expanded Medicaid under the Affordable Care Act (ACA) through a federal waiver that permitted state-mandated features, including an emphasis on primary care. We investigated the factors associated with Michigan primary care providers (PCPs)' decision to accept new Medicaid patients under Medicaid expansion.
Study Design: Statewide survey of PCPs informed by semistructured interviews.
Methods: After Michigan expanded Medicaid on April 1, 2014, we surveyed 2104 PCPs (including physician and nonphysician providers, such as nurse practitioners and physician assistants) with 12 or more assigned Medicaid expansion enrollees (response rate, 56%). To guide survey development and interpretation, we interviewed a separate group of 19 PCPs with Medicaid expansion enrollees from diverse urban and rural regions. Survey questions assessed PCPs' current acceptance of new Medicaid patients.
Results: Of the 2104 surveyed PCPs, 78% reported that they were currently accepting additional Medicaid patients; 58% reported having at least some influence on the decision. Factors considered very/moderately important to the Medicaid acceptance decision included practice capacity to accept any new patients (69%), availability of specialists for Medicaid patients (56%), reimbursement amount (56%), psychosocial needs of Medicaid patients (50%), and illness burden of Medicaid patients (46%). PCPs accepting new Medicaid patients tended to be female, minorities, nonphysician providers, specialized in internal medicine, paid by salary, or working in practices with Medicaid-predominant payer mixes.
Conclusions: In the era after Medicaid expansion, PCPs placed importance on practice capacity, specialist availability, and patients' medical and psychosocial needs when deciding whether to accept new Medicaid patients. To maintain primary care access for low-income patients with Medicaid, future efforts should focus on enhancing the diversity of the PCP workforce, encouraging healthcare professional training in underserved settings, and promoting practice-level innovations in scheduling and integration of specialist care.