“Ghost” Physicians Haunt Medicaid, Drive Access Gaps in Care

New research is sounding the alarm on "ghost" physicians in the US and their adverse impact on healthcare disparities, including access gaps and physician workload.

The Health Affairs journal published a new study on February 2, 2026, finding that nearly one-third of physicians who have enrolled in Medicaid don’t care for a single Medicaid patient.¹

“Low physician participation in Medicaid is a commonly cited reason for access gaps and unmet need in Medicaid,” Jane Zhu, MD, associate professor of medicine (general internal medicine and geriatrics) in the Oregon Health & Science University School of Medicine, said in a press release.² “If patients aren’t able to access the care they need, they may delay or forego care altogether, which is not only bad for patient outcomes, but also bad for the health system overall.”

Investigators also found that an additional one-third of health care providers enrolled in Medicaid see a high volume of patients, possibly overburdening HCPs. Forgoing or even delaying care can harm patients causing increased medical issues and driving up the costs for Medicare further.

As Zhu and colleagues noted, the amount of research dedicated to how participating physicians deliver care has been studied to a lesser degree than physicians' acceptance of Medicaid. Investigators sought to develop a more accurate understanding of the provider workforce available to Medicaid beneficiaries.

In this study, researchers matched physician enrollment files to Medicaid administrative claims from the period 2019–2021, focusing on 5 physician specialties:

1. Cardiology
2. Dermatology
3. Ophthalmology
4. Primary Care
5. Psychiatry

The analysis linked physician enrollment records to national Medicaid claims data from 2019–2021 using the Transformed Medicaid Statistical Information System (T-MSIS) Analytic Files. The Annual Provider file was used to identify physicians authorized to deliver care to Medicaid and Children’s Health Insurance Program (CHIP) beneficiaries, including enrollment status and effective dates, recognizing that authorization does not necessarily indicate service delivery. Outpatient billing activity was assessed using claims from the Other Services file.

During the study period, 68–89% of physicians were enrolled in Medicaid, however in 2021, nearly 28% delivered no care to Medicaid patients.

Participation in Medicaid varied widely by specialty:

• More than 40% of psychiatrists were “ghost” physicians who saw no Medicaid enrollees each year
• Primary care physicians were most likely to be high-volume “core” participants, although 26.3% what investigators termed “ghost” providers
• Cardiologists were the least likely to be “ghost” physicians with a rate of 17.9%

Medicaid engagement was not only varied among specialties but also varied over the years of the study. Over one-fourth of peripheral physicians, which was defined as those who see 1-10 Medicaid patients per year, increased their caseloads between 2019 and 2021.

Investigators highlight that “ghost” providers may have legitimate reasons for their lack of seeing Medicaid patients, including the hospitals or health systems requiring them to be enrolled, the COVID-19 pandemic, limited staffing, or even a change in their status, such as retiring.¹

“Patients may call providers who say they are enrolled in Medicaid, but those calls go nowhere,” Zhu said.² “People give up because those providers aren’t actually available to see them.”

Investigators also called attention to multiple limitations within their study to consider when interpreting results. First, the APR files are state-reported enrollment data, however, states may differ on how these files are submitted. Second, the study focused on physicians and not nonphysician clinicians who could have provided services. Sometimes, nonphysicians bill under the physician’s name. Third, the analysis was restricted to outpatient claims and did not include services from an inpatient setting.¹

References:

1. Zhu JM, Johnston KA, Hart K, Polsky D, McConnell KJ. 'Ghost' Physicians: More Than One-Quarter Of Physicians Enrolled In Medicaid Delivered No Care To Beneficiaries In 2021. Health Aff (Millwood). 2026;45(2):129-137. doi:10.1377/hlthaff.2025.00703

2. Robinson E. “Ghost” providers hinder access to health care for Medicaid patients. OHSU News. Published February 2, 2026. Accessed February 5, 2026. https://news.ohsu.edu/2026/02/02/ghost-providers-hinder-access-to-health-care-for-medicaid-patients