Research
Summary
Dr. Machado's research operates at the intersection of health economics, health policy, and health services research, with a particular focus on understanding how health system design influences health outcomes. Her work spans multiple methodological approaches and addresses critical questions about healthcare access, financing, and performance across different populations and health systems.
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Her recent landmark research on wealth and mortality has demonstrated that even the wealthiest Americans face higher mortality rates than their European counterparts, revealing fundamental differences in how health systems translate economic resources into health outcomes. This work, published in the New England Journal of Medicine, has garnered international media attention and policy discussion across multiple countries.
Dr. Machado's expertise in cardiovascular health economics encompasses the full spectrum from prevention to advanced interventions. Using the Health and Retirement Survey, she has examined how midlife wealth mobility affects long-term cardiovascular outcomes, while her work with clinical data from the United Network for Organ Sharing has analyzed evolving patterns in heart transplantation access, donor utilization, and the impact of comorbidities on transplant outcomes. Her pharmaceutical policy research has quantified how Medicaid expansion influenced access to life-saving cholesterol medications and, in her latest work, examines how multimarket contacts influence competition in statin price-regulated markets, providing insights into generic drug market structure and regulation.
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Her research portfolio extends to health system assessment and comparative analysis, including developing frameworks for evaluating political parties' health proposals and analyzing health workforce dynamics across multiple dimensions. Her foundational work on the economics of medical training developed conceptual models analyzing trade-offs between different types of healthcare providers, while her empirical research has examined physician workforce distribution across urban and rural areas and its implications for healthcare access. This workforce research has direct relevance to understanding healthcare demand patterns, for example in care settings where provider availability influences service utilization and patient outcomes. She has also pioneered work at the intersection of technology and healthcare financing, studying fraud detection in medical crowdfunding and examining how race and ethnicity influence healthcare crowdfunding success.
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Dr. Machado's behavioral health economics research explores pro-social behaviors in healthcare settings, including altruism in organ donation and blood donation systems. Her dissertation work analyzed the economics of blood donation systems.
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Her methodological versatility spans from econometric analysis of large administrative datasets to machine learning applications in healthcare fraud detection. This interdisciplinary approach has resulted in publications across premier medical journals (New England Journal of Medicine, JAMA family), health economics and health services research journals (Health Economics, Health Services Research), and computer science venues, demonstrating the broad impact and applicability of her research across multiple fields.
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See CV for publication details.
Featured Research
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Association Between Wealth and Mortality in the United States and Europe
with Ilias Kyriopoulos, John Orav, and Irene Papanicolas
Published April 2, 2025
N Engl J Med 2025;392:1310-1319
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Background
Amid growing wealth disparity, we have little information on how health among older Americans compares with that among older Europeans across the distribution of wealth.
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Methods
We performed a longitudinal, retrospective cohort study involving adults 50 to 85 years of age who were included in the Health and Retirement Study and the Survey of Health, Ageing, and Retirement in Europe between 2010 and 2022. Wealth quartiles were defined according to age group and country, with quartile 1 comprising the poorest participants and quartile 4 the wealthiest. Mortality and Kaplan–Meier curves were estimated for each wealth quartile across the United States and 16 countries in northern and western, southern, and eastern Europe. We used Cox proportional-hazards models that included adjustment for baseline covariates (age group, sex, marital status [ever or never married], educational level [any or no college education], residence [rural or nonrural], current smoking status [smoking or nonsmoking], and absence or presence of a previously diagnosed long-term condition) to quantify the association between wealth quartile and all-cause mortality from 2010 through 2022 (the primary outcome).
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Results
Among 73,838 adults (mean [±SD] age, 65±9.8 years), a total of 13,802 (18.7%) died during a median follow-up of 10 years. Across all participants, greater wealth was associated with lower mortality, with adjusted hazard ratios for death (quartile 2, 3, or 4 vs. quartile 1) of 0.80 (95% confidence interval [CI], 0.76 to 0.83), 0.68 (95% CI, 0.65 to 0.71), and 0.60 (95% CI, 0.57 to 0.63), respectively. The gap in survival between the top and bottom wealth quartiles was wider in the United States than in Europe. Survival among the participants in the top wealth quartiles in northern and western Europe and southern Europe appeared to be higher than that among the wealthiest Americans. Survival in the wealthiest U.S. quartile appeared to be similar to that in the poorest quartile in northern and western Europe.
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Conclusions
In cohort studies conducted in the United States and Europe, greater wealth was associated with lower mortality, and the association between wealth and mortality appeared to be more pronounced in the United States than in Europe.