TY - JOUR TI - Medicare Appointment Availability and Wait Times Vary Considerably Across Four Large US Urban Markets AU - Beetham, T AU - Marsh, T AU - Barnett, M.L AU - Aaron, R.M AU - Greenberg, E AU - Do Alexandra AU - Zhu, J.M JO - Health Affairs Scholar PY - 2026 VL - 4 IS - 3 DO - 10.1093/haschl/qxag054 UR - https://doi.org/10.1093/haschl/qxag054 AN - 41878001 AB - INTRODUCTION: Timely access to primary care is essential for Medicare beneficiaries. Amid growing workforce shortages and consolidation, little is known about whether and how organizational and market-level factors affect access. METHODS: We conducted a simulated-patient study of 444 primary care clinics in Chicago, Los Angeles, New York, and Portland to measure acceptance of new Medicare patients and wait times to the earliest appointment. RESULTS: Overall, 77.5% of clinics accepted new Medicare patients, ranging from 96.9% in Los Angeles to just 35.0% in Portland. Among accepting clinics, median wait times for a physician varied from 8 days in New York City to 61 days in Portland. In adjusted analyses, each additional practice site was associated with a 1.5-percentage-point lower probability of accepting new Medicare patients (P < 0.001), and hospital or health system-affiliated practices had waits about 15 days longer than independent practices, with prolonged delays concentrated in Portland. CONCLUSIONS: Findings highlight the importance of local organizational structure and market context in shaping access, with implications for workforce planning and access monitoring. KW - Medicare KW - primary care access KW - audit study KW - secret shopper KW - health system consolidation KW - wait times KW - industrial organization KW - health services research ER -