Addressing Inequalities in Health Care

Liang’s summer medical school project examined the prevalence of receiving annual eye screenings among South Korean adult patients with type 2 diabetes and how access to that care differed across demographic and socioeconomic groups over time. The goal was to investigate why screening rates for diabetic retinopathy, a complication of type 2 diabetes, remain low in South Korea, despite the country having universal health insurance coverage and guidelines that recommend annual eye screenings to prevent this leading cause of blindness.

He worked on this project with co-advisors Eggleston and Young Kyung Do, a professor in Seoul National University’s Department of Health Policy and Management and AHPP’s inaugural postdoctoral fellow. They found that lower-income patients with diabetes experienced barriers to quality diabetes care and had lower access to annual diabetes-related eye screenings.

For Liang, these results underscored a deeper lesson: even strong health systems with universal health insurance coverage have structural socioeconomic inequities that leave vulnerable groups behind. The findings helped solidify his conviction that improving health care requires more than clinical training alone. 

The project culminated in Liang’s presentation of the findings at the 2021 AcademyHealth Annual Research Meeting and spurred a new sense of purpose. ”It grew into a life-changing journey at Stanford,” Liang says.

That journey has led him to collaborate with researchers from around the world, particularly in Japan, Korea, and China, utilizing large-scale data to advance population health and applying population health methods to research topics ranging from maternal and child health to mental health, aging, and inflammatory skin diseases.

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Liang in South Korea. Photo courtesy of Richard Liang.

From Research to Health Policy Impact

Over the years, Liang evolved from a mentee of Eggleston into a collaborator on projects in Korea and elsewhere. As COVID-19 disrupted health services worldwide, he joined Eggleston and a team of researchers in studying the impact of the pandemic on chronic disease care in India, China, Hong Kong, Korea, and Vietnam. Their findings showed that marginalized and rural communities in those countries were hit especially hard, with negative consequences for population health that reached far beyond those directly infected with the virus.

He and Eggleston also co-authored a study on preferences for telemedicine services among patients with diabetes and hypertension in South Korea during the early COVID-19 pandemic. The research drew the attention of the Prime Minister’s Office in Korea, which used it to guide national policy on telemedicine, a field still lacking a formal legal framework in the country.

For Liang, it was proof of the available opportunities to make tangible improvements in population health by combining rigorous research with policy engagement and drawing on insights across medicine, public health, and the social sciences.

“As a medical student researcher with experiences across different East Asian countries, I witnessed firsthand many pressing challenges in health and society, from rapidly aging populations to rising rates of chronic diseases,” he says. “To tackle these issues holistically, there is a growing need to bring together diverse perspectives, but regional collaborations in medical and public health research have been scarce, and rarer still between the biomedical and social sciences.”

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Liang in China on a field visit during a 2025 summer seminar co-taught by Professors Eggleston and Williams. Photo courtesy of Richard Liang.

A Second Academic Home

Eggleston describes Liang as a model of interdisciplinary scholarship. In addition to medical school and doctoral research, he has carved out space to pursue his passion for East Asian studies. He has taken classes with APARC and affiliated faculty on topics ranging from health and politics in modern China to historical and cultural perspectives on North Korea, science and literature in East Asia, and tech policy, innovation, and startup ecosystems in Silicon Valley and Japan.

“The various classes and seminars I’ve attended through APARC, and subsequently as an East Asian Studies master’s student, have helped me think more critically about how the science and practice of medicine impact policy and society, and vice versa,” Liang says. Thanks to these experiences, he also found “a second academic home away from the medical school — a community that shares the recognition of the need to strengthen dialogue and cooperation across the Pacific and that actively encourages the interdisciplinary environment necessary to make my aspirations a reality.”

Most recently, he participated in a summer seminar on AI-enabled global public health and population health management, co-taught by Eggleston and Michelle Williams, a professor of epidemiology and population health at Stanford’s School of Medicine. Offered via the Stanford Center at Peking University, this three-week seminar focused on advancing global health through cross-cultural collaboration and the application of cutting-edge technology in population health and health policy decision-making. 

“During this program, I not only got to share my experiences from conducting population health research across East Asia, but also learn from and alongside fellow students across different disciplines, spanning from international relations to computer science,” Liang notes. He especially enjoyed meeting local Chinese graduate students and providing feedback and near-peer mentorship as an upper-year graduate student.

The seminar also led to exploring additional opportunities for research collaborations to study the implications of long-term annual health screenings across China. Liang, Eggleston, and Williams plan to expand this collaborative work.

Preparing to Become a Better Care Provider

Liang’s work across borders and disciplines not only advances research but also deepens the perspective of cultural humility he brings to his future role as a physician.

“The cross-cultural experiences and fruitful academic exchanges I’ve learned through as a Stanford graduate student not only inform my research in different countries, but also help prepare me to become a better care provider for my future patients,” he says.

For his achievements, Liang has earned multiple honors, including a Young Investigator Collegiality Award from the International and Japanese Societies for Investigative Dermatology, the Critical Language Scholarship in Korean from the U.S. Department of State, and the Stanford Center for Asian Health Research and Education Seed Grant.

He is looking forward to finishing medical school, attending a residency program, and continuing an interdisciplinary career that advances human health and well-being.

Reflecting on the fleeting nature of student life, his advice to fellow students is to remember that “Your time as a Stanford student can really fly by, so make sure to explore the opportunities that speak to you and offerings across the university, by organizations like APARC and the Freeman Spogli Institute for International Studies. The Bechtel International Center’s Office of Global Scholarships and the Hume Center for Writing and Speaking are also wonderful resources to get started.”

It is advice he has embodied himself, building a career at the intersection of medicine, public health, and East Asian studies, one project at a time.

The Walter H. Shorenstein Asia-Pacific Research Center (APARC) is pleased to invite applications for a suite of fellowships in contemporary Asia studies to begin in fall quarter 2026.

The Center offers postdoctoral fellowships that promote multidisciplinary research on Asia health policy, contemporary Japan, and contemporary Asia broadly defined, as well as postdoctoral fellowships and visiting scholar positions with the Stanford Next Asia Policy Lab and a visiting fellow position on contemporary Taiwan. Learn more about each opportunity and its specific application requirements:

2026-27 Asia Health Policy Program Postdoctoral Fellowship

Hosted by the Asia Health Policy Program at APARC, the fellowship is awarded to one recent PhD recipient undertaking original research on contemporary health or healthcare policy of high relevance to countries in the Asia-Pacific region, especially developing countries. Appointments are for one year beginning in fall quarter 2026. The application deadline is December 1, 2025.

2026-27 Japan Program Postdoctoral Fellowship

Hosted by the Japan Program at APARC, the fellowship supports research on contemporary Japan in a broad range of disciplines, including political science, economics, sociology, law, policy studies, and international relations. Appointments are for one year beginning in fall quarter 2026. The application deadline is December 1, 2025.  

2026-27 Shorenstein Postdoctoral Fellowship on Contemporary Asia

APARC offers two postdoctoral fellowship positions to junior scholars for research and writing on contemporary Asia. The primary research areas focus on political, economic, or social change in the Asia-Pacific region (including Northeast, Southeast, and South Asia), or international relations and international political economy in the region. Appointments are for one year beginning in fall quarter 2026. The application deadline is December 1, 2025. 
 

2026-27 Taiwan Program Visiting Fellowship

Hosted by the Taiwan Program at APARC, the fellowship is awarded to one mid-career to senior-level expert with extensive experience studying contemporary Taiwan. The fellowship research focus is on issues related to how Taiwan can meet the challenges and opportunities of economic, social, technological, environmental, and institutional adaptation in the coming decades, using a variety of disciplines, including the social sciences, public policy, and business. The application deadline is March 1, 2026.  
 

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.

Despite technological breakthroughs, healthcare inequality remains a pressing public health challenge across developed and developing nations. Low levels of income or education mobility can exacerbate socioeconomic disparities, leaving children from disadvantaged families with fewer opportunities to improve their social and economic prospects. Moreover,  children in families with low-income backgrounds are also more likely to experience poor health outcomes, perpetuating a cycle of disadvantage.

Huixia Wang, a visiting scholar at Shorenstein APARC, sees this phenomenon as an opportunity to better understand the dynamics of intergenerational health and how to interrupt patterns of persistent health inequalities across generations. Her research aims to identify potential interventions to improve health outcomes in developing regions.

An associate professor at Hunan University, Wang has spent the 2024 fall quarter at APARC. She recently presented her research on the intricate dynamics of intergenerational health metrics, particularly in China and Indonesia. Watch her talk, “Intergenerational Persistence of Self-Reported Health Status and Biomarkers in Indonesia,” on our YouTube channel.

Barriers to Intergenerational Health

While much has been written about the transmission of income and education across generations, “much less is known about how health is passed down between generations," Wang notes, highlighting a gap in the existing research. Emphasizing that health is a crucial factor in determining overall well-being, as it affects everything from mental health to economic productivity and social mobility, she asserts that good health is linked to better educational outcomes, higher earning potential, and improved labor market performance. Poor health, on the other hand, is associated with lower educational attainment, reduced employment prospects, and higher rates of chronic illness.

Wang’s research approach centers on recognizing the multiple challenges in implementing maternal health-oriented policies. Having identified limited access to healthcare services as a significant barrier, she considers how, in many low-income and rural areas, “access to quality healthcare is constrained by poor infrastructure, lack of transportation, and shortages of healthcare professionals, making it difficult for pregnant women to receive essential care.”

Another obstacle is the prohibitive cost of healthcare. In countries where maternal health services are not subsidized or free, the financial burden of out-of-pocket expenses for transportation, medications, and other related costs can prevent women from accessing necessary care. Furthermore, Wang shows that low levels of maternal health education can contribute to poor health-seeking behaviors. “Many women may not recognize the warning signs of complications, may not fully understand the importance of prenatal care, or may be unaware of their rights to healthcare services,” she says.

Measuring Health Outcomes Across Generations

Wang acknowledges the difficulties in studying intergenerational health mobility, as it cannot be neatly defined and measured by observable metrics such as income or education. Health is much more subjective and varies from person to person. To gauge health outcomes, researchers must therefore rely on diverse and sometimes imprecise indicators, such as the presence of chronic diseases.

Moreover, to examine intergenerational mobility, researchers need data that includes health information for both parents and children. Such datasets are not always readily available, and those that do exist often lack the necessary granularity and long-term tracking to provide meaningful insights.

To overcome these challenges, Wang draws on a variety of panel data that tracks individuals over time, as well as survey data and self-reported status. For Wang, longitudinal studies are crucial for understanding how health disparities manifest and evolve over time. 

Using data from the Indonesia Family Life Survey, she combines subjective measures like self-reported health and objective measures such as pulse, BMI, hypertension, and anemia to capture a more complete picture of health mobility. This approach expands beyond previous studies, which typically relied on fewer health indicators and focused on developed countries. Her study includes a broad range of health variables and provides a unique look at the role of gender and socioeconomic factors in shaping health outcomes across generations.

Wang uses two primary methods for measuring intergenerational health mobility: one following the Intergenerational Health Association, which regresses children's health outcomes on those of their parents, and rank-rank regressions, which examine the persistence of health outcomes by analyzing percentile ranks. These techniques, adapted from income mobility research, allow her to assess health persistence and mobility across generations.

Future Directions and Policy Impact

Wang’s time at APARC has been instrumental in shaping and refining her research. "The opportunity to engage with experts from various fields [...] opened my eyes to new ways of thinking about my research," she shared. "The collaborative environment at APARC also made me realize how much I can learn from perspectives outside my immediate area of focus.”

Wang credits Stanford’s vibrant academic environment, with its rich array of seminars and talks, to broadening her understanding of Southeast Asian health systems, a subject she was less familiar with. She expressed gratitude to APARC faculty for their “invaluable guidance for both my research and my life at Stanford.” In particular,  APARC’s Asia Health Policy Program Director Karen Eggleston “dedicated a significant amount of time to advising my work, introducing me to key researchers in my field, and sharing the valuable resources that I might benefit from on campus,” Wang said.

Looking ahead, she is excited to continue exploring the role of health in intergenerational mobility, particularly in the Southeast Asian context, and plans to expand her research into the health effects of pollution, an area she has already begun to investigate. Wang also hopes to contribute to policymaking that addresses health inequality. By providing a deeper understanding of how health disparities are perpetuated across generations, she aims to inform policies that could improve health outcomes and reduce inequality in developing countries.

Wang’s research on intergenerational health mobility offers a fresh and much-needed perspective on the crucial yet understudied role of health in social mobility. She hopes her research helps policymakers and scholars address health inequalities that perpetuate socioeconomic disadvantage across generations.

The Walter H. Shorenstein Asia-Pacific Research Center (APARC) is pleased to invite applications for a host of fellowships in contemporary Asia studies to begin in Autumn quarter 2025.

The Center offers postdoctoral fellowships that promote multidisciplinary research on Asia-focused health policy, contemporary Japan, and contemporary Asia broadly defined, postdoctoral fellowships and visiting scholar positions with the Stanford Next Asia Policy Lab, and a fellowship for experts on Southeast Asia. Learn more about each opportunity and its eligibility and specific application requirements:

Asia Health Policy Program Postdoctoral Fellowship

Hosted by the Asia Health Policy Program at APARC, the fellowship is awarded to one recent PhD undertaking original research on contemporary health or healthcare policy of high relevance to countries in the Asia-Pacific region, especially developing countries. Appointments are for one year beginning in Autumn quarter 2025. The application deadline is December 1, 2024.

Japan Program Postdoctoral Fellowship

Hosted by the Japan Program at APARC, the fellowship supports research on contemporary Japan in a broad range of disciplines including political science, economics, sociology, law, policy studies, and international relations. Appointments are for one year beginning in Autumn quarter 2025. The application deadline is December 1, 2024.  

Shorenstein Postdoctoral Fellowship on Contemporary Asia

APARC offers two postdoctoral fellowship positions to junior scholars for research and writing on contemporary Asia. The primary research areas focus on political, economic, or social change in the Asia-Pacific region (including Northeast, Southeast, and South Asia), or international relations and international political economy in the region. Appointments are for one year beginning in Autumn quarter 2025. The application deadline is December 1, 2024.