As countries confront rising health care spending, policymakers everywhere face a key question: Who benefits from these spending increases?

Consider South Korea, a nation that has sharply increased its per capita health care spending over the past decade, delivering reasonable value in improving health outcomes as measured by rising life expectancy and a reduced overall disease burden. Yet, not all South Koreans reap equal rewards from the country’s health investments, according to a new study. Rather, adults in the lowest-income quintile receive the least health gains for every dollar spent on their care.

Published in the journal Health Affairs Scholar, the study reveals stark income-based disparities in the value of health care — defined as health gains relative to spending — among South Korean adults. The research systematically quantifies how efficiently health spending translates into longer, healthier lives across income groups in South Korea, providing insights into the distribution of health gains relative to health care spending.

“While earlier research often examined disparities in access, utilization, or outcomes separately, our analysis provides a more integrated assessment by jointly examining health care costs and health gains,” explains the research team, including Stanford health economist Karen Eggleston, the director of the Asia Health Policy Program (AHPP) at APARC. Eggleston’s co-authors are Sungchul Park, an associate professor in Korea University’s Department of Health Policy and Management and an incoming visiting scholar with AHPP; Young Kyung Do, a professor in Seoul National University’s Department of Health Policy and Management and AHPP’s inaugural postdoctoral fellow; and David Cutler, the Otto Eckstein Professor of Applied Economics at Harvard University. 

Their findings are sobering: between 2010 and 2018, South Korean adults in the lowest income quintile derived the least value from increased health spending compared to those in the middle- and higher income quintiles, suggesting a system that underserves the poorest population.

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Poorer Health, Smaller Gains

Between 2010 and 2019, per capita health care spending in Korea increased from $1,211 to $1,903, growing nearly 6 percent annually. During that decade, life expectancy climbed from 80.5 to 83.7 years, while disability-adjusted life years – expressed as the number of years lost due to ill-health – declined significantly. These measures seemingly suggest health spending has yielded solid returns in terms of improved health outcomes.

Yet stark income inequality persists in Korea. The country has both the highest old-age poverty rate and the largest share of out-of-pocket medical expenses among OECD countries. Does rising health spending benefit all segments of society equally?

To answer this question, the researchers analyzed trends in health spending and outcomes across income quintiles (excluding the bottom 10 percent of the household income distribution) from 2010 to 2018.

They measured health care spending as total medical expenditures, including costs for inpatient and outpatient services, emergency services, and prescription medications. All spending measures were adjusted for inflation and are reported in 2021 US dollars. To asses health outcomes, they used three indicators: (1) health-related quality of life, which relies on standard questionnaires to measure individuals’ perceived physical and mental health over time; (2) life expectancy, calculated using life table methods based on enrollment data from the national health insurance system; and (3) quality-adjusted life expectancy (QALE) at age 25, a measure that reflects both longevity and the quality of life during those years – an essential consideration when evaluating the effectiveness and equity of health care systems. To quantify the value of health care across income groups, the researchers applied statistical methods.

They found that adults in the lowest-income quintile experienced the smallest relative improvement in QALE over time: an increase of 0.7 years, compared with 1.4 years in the second and third quintiles, 1.3 years in the fourth, and 1.2 years in the highest quintile. Translated into a value estimate, adults in the lowest income quintile incurred $78,209 per QALE; in contrast, adults in the second through highest income quintiles achieved greater value estimates of $47,831, $46,905, $31,757, and $53,889, respectively. Thus, the most efficient gains in both longevity and quality of life were in the middle-income groups.

“We found that per capita spending was similar across income groups, but the lowest-income quintile experienced much smaller gains in QALE,” Eggleston and her collaborators write. 

Reflecting the principle of diminishing returns, “these findings highlight structural inequities in the South Korean health system and emphasize the need for targeted policies to promote equitable health care value.” 

Why Spending Does Not Equal Value

While the study did not identify causal pathways, secondary data suggest two plausible explanations for the results: poorer baseline health and greater unmet needs.

The data indicate that adults in the lowest-income quintile had significantly higher rates of chronic disease, disability, behavioral risk factors such as smoking and obesity rates, and mental health issues. These factors make it more difficult to achieve health gains.

Moreover, adults in the lowest-income quintile were less likely to receive preventive services, with markedly lower rates of medical checkups and cancer screenings. “Despite greater health needs, these adults faced persistent barriers to accessing care, particularly financial constraints,” the researchers say.

Notably, the highest value of health spending was not observed among adults in the highest-income group. One explanation is that this group may consume more low-value or marginally beneficial health services.

Policy Implications: Efficiency with Equity

Eggleston and her co-authors emphasize “the need for health policy in South Korea to prioritize both equity and value.” They highlight the following targeted strategies to improve efficiency and fairness:

• Invest in high-value services that link spending to meaningful health outcomes:
  • Improve access to high-value preventive and primary care services by expanding financial protections, particularly for lower-income groups.
  • Improve overall system efficiency by reducing the overuse of low-value health care services.
• Pair health care reform with broader social policies: Coordinate efforts to address upstream factors tied to health disparities, such as income inequality.
• Aim for improvements across the entire population: Implement evidence-based clinical appropriateness guidelines to ensure health care spending yields meaningful and equitable results.

While focused on South Korea, the study’s findings illuminate how income inequality interacts with health system designs and carry lessons for other countries.

“In countries with greater income inequality and fragmented health systems, such as the United States, disparities in health care value may be even more pronounced,” the co-authors write.

As South Korea and other countries continue to invest heavily in health care, the study highlights the urgency of improving the distribution and impact of that increased spending. Without focused reforms, it risks entrenching existing inequities rather than alleviating them.

Stanford student JB (Jong Beom) Lim and recent alumni Darren Hall, Yoojung Lee, E Ju Ro, and Maleah Webster all had the opportunity to work as research assistants with the Stanford Next Asia Policy Lab (SNAPL). They also have another thing in common: all are heading next fall to prestigious programs where they will embark on their doctoral training in law, political studies, and sociology.

Housed at the Walter H. Shorenstein Asia-Pacific Research Center (APARC) and led by sociologist Gi-Wook Shin, the William J. Perry Professor of Contemporary Korea and a senior fellow at the Freeman Spogli Institute for International Studies, SNAPL addresses emergent social, cultural, economic, and political challenges facing Asia-Pacific countries and guides effective U.S. Asia policies through interdisciplinary, comparative, and data-driven research. A core mission of the lab, which Shin founded in summer 2023, is to support and mentor the next generation of Asia scholars through its fellowship opportunities and research assistantships.

“The success of our former research assistants demonstrates exactly the kind of impact I envisioned when I launched SNAPL,” says Shin, who also serves as the director of APARC and the center’s Korea Program and Taiwan Program. “Our lab is a space where young researchers engage deeply with urgent issues in Asian affairs and U.S.-Asia relations while building the skills and networks to carry them forward as they pursue advanced academic training. I am tremendously proud of what our bright young scholars have achieved – they will be leaders in Asian studies.”

​​In its short history, SNAPL has already seen previous team members advance to graduate studies at top institutions. These include current PhD students Kelsi Caywood (sociology, University of Michigan); Sean Chen (economics, Princeton University); Haley Gordon (sociology, Stanford University); and Vineet Gupta (sociology, Northwestern University).

We spoke with Darren, Yoojung, JB, E Ju, and Maleah about their experience at SNAPL, next steps in their academic journeys, and advice for new students. The responses below were slightly edited for clarity and style. 

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Darren Hall 

Darren Hall graduated from Stanford in 2023 with a bachelor’s degree in East Asian studies. Darren received multiple department awards for his undergraduate work, including the Kung-Yi Kao Prize for Outstanding Progress in the Study of the Korean Language and the James J.Y. Liu Prize for Outstanding Writing in an East Asian Languages and Cultures Course.

After graduation, he was a research assistant for the “Nationalism and Racism in Asia” track at SNAPL. In that role, he conducted a literature review, consulted with the project team to improve research methods, and helped conceptualize and develop the foundation for the project’s eventual publication.

“SNAPL not only provided me with mentorship but also an opportunity to investigate the interplay of nationalism and racism throughout Asia,” he says.

After his time at SNAPL, Darren worked as a corporate legal assistant at BraunHagey & Borden LLP, where he supported a team of attorneys through multi-million dollar transactions.

In fall 2025, Darren will begin his first year at Yale Law School. He plans to explore international conflict resolution and continue to develop his advocacy for underrepresented communities. Darren intends to become an attorney who prioritizes compassion and justice.

Yoojung Lee

Yoojung Lee graduated from Stanford in 2023 with a master’s degree in East Asian studies. In the coming fall quarter, she will embark on her new path as a doctoral student in sociology at Harvard University. Her research centers on a comparative investigation of political polarization through the intersecting lenses of gender, race, and ethnicity. 

Her time at SNAPL, while working for the “Nationalism and Racism in Asia” research track, and the generosity and depth of insight of the lab’s community of scholars have left a lasting imprint on Yoojung and broadened her intellectual framework. “The diversity of experiences and perspectives within the lab has profoundly reshaped how I engage with the world, not only in terms of how I think, but also in what I prioritize, whose voices I amplify, and how I approach the questions that guide my research.”

Yoojung also credits the SNAPL community for advancing her personal development. “The collaborative spirit of the lab and the dedicated mentorship I’ve received have influenced how I navigate challenges, engage with complexity, and embrace uncertainty. Within this space, I’ve learned to view setbacks as opportunities for growth and stay grounded in the deeper purpose behind my work. It is also here that the idea of pursuing a PhD, once abstract and distant, transformed into a tangible, deeply personal goal.”

The clarity, conviction, and sense of direction Yoojung feels about her academic path are inseparable from the lessons, experiences, and support she has found at SNAPL. “For all of this, I am eternally grateful: not only for the intellectual enrichment, but for the sense of belonging, purpose, and hope that SNAPL has given me. These are the gifts I will carry with me into my PhD and beyond.”

JB Lim

JB (Jong Beom) Lim will graduate this spring from Stanford with a master's degree in computer science and bachelor's degrees in mathematical and computational science and international relations. He has received interdisciplinary honors from the Center for International Security and Cooperation, with his undergraduate thesis recognized by the Center for East Asian Studies and the Hoover Institution.

In fall 2025, JB will begin his doctorate as a Raymond Vernon Fellow at Harvard University's Department of Government. He will examine how economic interdependence shapes national security strategies, focusing on how domestic interest groups influence foreign policy decisions regarding technology and trade. As part of his research, JB also hopes to develop quantitative methods in machine learning and causal inference, leveraging large-scale granular data.

At SNAPL, JB assisted with the “U.S.-Asia Relations” research track. “Working at SNAPL introduced me to cutting-edge political science research and allowed me to build novel datasets on congressional speeches and scholarly networks,” he says. “This experience sharpened my methodological skills and taught me to approach complex questions creatively and with rigor.”

JB’s advice to current students? “Embrace interdisciplinary research – it opens unexpected doors and broadens your understanding of global challenges.”

E Ju Ro

At Stanford, E Ju Ro earned her master's and bachelor's degrees in sociology, a minor in philosophy, and honors in Ethics in Society. Beginning in the coming fall quarter, she will attend New York University Law School. She is particularly interested in international human rights and critical legal studies. 

As a research assistant with SNAPL, E Ju had the opportunity to work on the “Nationalism and Racism in Asia” track, specifically on a study analyzing the discourse of state party reports submitted to the United Nations Committee on the Elimination of Racial Discrimination (CERD) by 16 Northeast, Southeast, and South Asian countries.

“It was fascinating to examine the reports various Asian governments sent CERD, as I could see how their specific cultural and historical contexts shaped the ways they dealt with (or did not deal with) racial issues,” says E Ju. “While pursuing sociology studies at Stanford, I’d felt that most of my research experience and classes had focused on the United States, so this was a refreshing chance to look at the construction of race across time and borders."

Maleah Webster

At Stanford, Maleah Webster received a bachelor's degree in international relations with honors and distinction. She concentrated on East and South Asia and social development and human well-being.

This coming fall, Maleah will begin a doctorate in sociology at Stanford. Her research investigates how migrant communities navigate identity, belonging, and access to resources in contexts where ethnic homogeneity is closely tied to national identity. She focuses on institutions as key sites where integration is negotiated and contested, whether through policy, discourse, or lived experience. Currently, she conducts fieldwork in South Korea, using interviews, surveys, and policy analysis to decipher how multiculturalism is defined and experienced in real-world settings.

Maleah describes her experience working as a research assistant with SNAPL as a highly valuable part of her time at Stanford. She, too, worked on the lab’s “Nationalism and Racism in Asia” research track. “It gave me a real sense of how cross-national research can inform policy in nuanced and meaningful ways. Being part of SNAPL helped me see how institutions don’t just implement policy – they help define who counts, who belongs, and who gets overlooked.”

Her tip for new students is to “take the initiative to get involved with research early, especially in interdisciplinary spaces like SNAPL. You never know what opportunities (or career trajectories) it might open up.”

The Shorenstein Asia-Pacific Research Center (APARC) is delighted to share that Stanford Sociologist Gi-Wook Shin, the William J. Perry Professor of Contemporary Korea, director of APARC, and founding director of the Korea Program at APARC, is the recipient of the Korean American Achievement Award for his contributions to promoting Korean Studies, strengthening U.S.-Korea relations, and fostering transnational collaboration. The award was presented at the 122nd anniversary celebration of Korean American Day in San Francisco on January 11, 2025.

The Korean American Achievement Award recognizes individuals who have made outstanding contributions to the Korean American community’s academic, cultural, and civic development. Shin, a historical-comparative and political sociologist who is also a senior fellow at the Freeman Spoglli Institute for International Studies, has dedicated himself to addressing Korea’s contemporary challenges and bridging the United States and Korea. His work combines rigorous research with actionable policy insights, focusing on democracy, nationalism, societal development in Korea, migration, and international relations. He is also a sought-after media commentator on Korean affairs and U.S.-Korea ties.

Shin is the author and editor of 25 books and numerous articles. His most recent book is Korean Democracy in Crisis: The Threat of Illiberalism, Populism, and Polarization (Shorenstein APARC, 2022). Stanford University Press will publish his next book, The Four Talent Giants: National Strategies for Human Resource Development Across Japan, Australia, China, and India, in July 2025.

Under Shin’s leadership as its founding director, the Korea Program has become a renowned Stanford hub for interdisciplinary research and dialogue on contemporary Korea. The program celebrated its 20th anniversary in 2022, marking two decades of promoting education and exchange on Korea’s political, economic, and social evolution. Beyond academia, the program is a platform for fostering the next generation of leaders dedicated to advancing Korea’s future and strengthening Korea-U.S. ties.

Shin also spearheads the Stanford Next Asia Policy Lab (SNAPL), an initiative committed to addressing emergent social, cultural, economic, and political challenges in Asia through interdisciplinary, policy-relevant, and comparative studies and publications.

The Korean American Day commemorates the arrival of the first Korean immigrants in the United States on January 13, 1903. The 122nd anniversary of Korean American Day was co-hosted by the Consulate General of the Republic of Korea in San Francisco, the San Francisco & Bay Area Korea Center, and Korean organizations in Northern California. The event was held at the San Francisco & Bay Area Korea Center.

Congratulations to Professor Shin on this well-deserved honor! It is a testament to his leadership and contributions that enrich the Korea Program and APARC’s mission to deepen the understanding of Asia and strengthen U.S.-Asia relations.