ABSTRACT
Disparities in health within the U.S. are pervasive and, for some populations, widening. High-quality primary
care plays an important role in the prevention, diagnosis and management of the many chronic health
conditions that contribute to health disparities among older adults. Primary care in the U.S., however, is
threatened. Even before COVID-19, the per-capita supply of primary care physicians was falling and varied
dramatically by county, threatening rural and other less-advantaged communities. Little is known about how
access to high-quality primary care has changed in recent years—including changes in access associated with
the COVID-19 pandemic—or about the policy-, system-, or practice-level factors that are associated with better
quality of primary care for older adults. These gaps in understanding have hindered our ability, as a nation, to
provide the best care to older adults. This project will address this need by drawing on a unique national
dataset that includes annual information on the ownership and staffing of all U.S. primary care practices from
2015–2024, linked Medicare claims data, and surveys of nationally representative samples of these practices
conducted in 2017 and 2022. Work in this project will entail: Aim 1: Examine U.S. trends in access to primary
care for Medicare beneficiaries in traditional Fee-for-Service and Medicare Advantage and determine how
these trends varied for less-advantaged populations. The team will conduct repeated cross-sectional studies of
access to primary and relevant subspecialty care for Medicare enrollees and how trends in access to care
varied for less-advantaged populations. Aim 2: Identify the policy-, system-, and practice-level factors
associated with better processes and outcomes of care for Medicare beneficiaries, with a focus on those with
fewer social and economic advantages. The team will take advantage of the substantial differences across
states, delivery systems, and physician practices in the implementation of initiatives intended to improve and
support primary care to apply differences-in-differences approaches to identify potentially high impact factors.
Aim 3: Conduct qualitative research to deepen our understanding of the underlying barriers and facilitators to
improving primary care for less advantaged populations. Under this aim, the team will conduct key informant
interviews with experts on policy, primary care and the safety net to deepen our understanding of current
challenges and opportunities facing safety net practices. The team will then purposively sample practices that
participated in the 2022 survey that serve economically less-advantaged and minoritized populations and
conduct in-depth qualitative interviews with their leaders and staff. Findings across these three aims will be
triangulated to develop recommendations that can assist practice leaders, health system leaders, and
policymakers in improving primary care and reducing health disparities for older adults.