People

Rita Hamad, MD, PhD, is the Director of the SPHERE Center and the Harvard Center for Population and Development Studies. She is a professor in the Department of Social and Behavioral Sciences at Harvard T.H. Chan School of Public Health. Dr. Hamad spearheads a research agenda to examine the effects of social and economic policies on health disparities across the life course, with the goal of informing state and national policymaking. She specializes in applying quasi-experimental epidemiologic and econometric methods and the linkage of large survey and administrative data. This work involves collaborations with other research teams throughout the U.S. and internationally. She also provides consultations to local and federal policymakers on the design and impact of social policies to promote health equity.

Abdinasir Ali, PhD, MPH, is an assistant professor at the University of Nevada, Reno, School of Public Health. He received his PhD in Health Services and Policy, with a focus on health economics, from the University of Iowa and completed a postdoctoral fellowship in the Department of Social and Behavioral Sciences at the Harvard T.H Chan School of Public Health. Ali is a health economist and health services researcher whose work uses quasi-experimental designs and statistical and econometric methods applied to administrative data and surveys. His research focuses on understanding the effects of housing policies on health and health care use, and on examining the links between housing security, housing quality, poverty, and health status. Ali’s most recent work has been focused on state and federal social and economic support policies to understand their effects on the health of low-income households. At the SPHERE Center, he is examining the impacts of income support policies on health and well-being of young adults.

Daniel Collin, MPH, is a Senior Statistical Analyst and has worked at the SPHERE Center since completing his MPH in Epidemiology/Biostatistics from the UC Berkeley School of Public Health in 2018. He is currently working on examining how the earned income tax credit and other economic policies affect health and health behaviors. In his free time, he enjoys cycling, hiking, camping, and going to the movies and music venues.

Emily C. Dore, PhD, MPH, MSW, is an Assistant Professor at Tufts University School of Medicine. She earned her PhD in sociology from Emory University and completed her postdoctoral research at the SPHERE Center. Her research examines macro-level determinants of health with a goal of informing policies that decrease health inequities. More specifically, her work evaluates the short and long-term effects of social safety net generosity (i.e., benefit levels, administrative burdens) on health and program participation. Another area of research includes assessing the role of state-level structural oppression in shaping population health and health disparities, including structural sexism and structural classism. She continues to work with the SPHERE Center on social safety net projects, as well as research on local pandemic-era policies and health using the US COVID-19 County Policy (UCCP) Database.

Else Foverskov, PhD is an assistant professor at the University of Copenhagen. She completed a postdoctoral research fellowship at the SPHERE Center. She continues to work with the Center to examine the effects of neighborhood socioeconomic characteristics on health among a group of refugees in Denmark who were quasi-randomly assigned to neighborhoods of varying socioeconomic disadvantage upon arrival. Her broader research evaluates how social policies can help reduce health disparities. She holds a master’s degree in sociology and a PhD in social epidemiology from the University of Copenhagen, Denmark. In her free time, Else enjoys spending time with her family in Copenhagen’s many fantastic public spaces.

Kaitlyn Jackson, MPH, has worked at the SPHERE Center for the last 4 years as a Senior Statistical Analyst. She has contributed to a diverse portfolio of research projects, including quasi-experimental analyses of social policies, like Sugar-Sweetened Beverage Taxes, and expansions to SNAP, on maternal and mental health through leveraging nationally representative health datasets. She has also assisted with primary data collection and program management for the Assessing California Communities’ Experiences with Safety Net Supports Survey (ACCESS) study and Targeting Access and Knowledge of EITC Utilization and Policies (TAKE-UP) study. Prior to SPHERE, Kaitlyn spent 3 years working Latin America and competed her master’s degree in public health from the University of California Berkeley in 2018 during which she focused her graduate studies on addressing socio-economic and environmental determinants of chronic disease within vulnerable populations, including investigating chronic kidney disease incidence in Jalisco, Mexico. Kaitlyn loves outdoor activities like hiking, backpacking, and traveling, and also enjoys cooking, water coloring, and spending quality time around New England with friends and family!

Deborah Karasek, PhD, MPH, is an assistant professor at Oregon Health Sciences University/Portland State University School of Public Health. She earned her MPH and PhD in Epidemiology from the University of California Berkeley, School of Public Health, and completed a Transdisciplinary Postdoctoral Fellowship with the Preterm Birth Initiative at UCSF.  She brings expertise in research design, implementation, and analysis to her work studying social determinants of perinatal and reproductive health. Her research applies a health equity lens to explore how economic insecurity, neighborhood housing conditions, and social policy impact the health and well-being of pregnant women and their families. She works with the SPHERE Center on evaluating the effects of the earned income tax credit and child tax credit on birth outcomes. She’s the mama of two young boys who keep her busy outside of work.

Min Hee Kim, PhD, is an assistant professor at Rutgers University, having completed her postdoctoral fellowship at the SPHERE Center. She received her PhD in Sociology and Social Work from the University of Michigan. Her work focuses on social and spatial determinants of mental and cognitive health in aging populations. Dr. Kim examines how neighborhood contexts impact clinical, social, and psychological health outcomes using large-scale data, including national surveys, census data, and administrative records. She is interested in developing and implementing innovative place-based social policies to reduce cognitive health risk among vulnerable populations. During her postdoctoral training, she is collaboratively investigating the effects of area deprivation on dementia and its vascular risk factors among a cohort of immigrants to Denmark. She is also involved in projects examining other social policies’ effects on health by leveraging natural experiments. Outside her work, she enjoys spending time with her family.

Matthew Lee, PhD, is a postdoctoral research fellow at the Government Performance Lab at the Harvard Kennedy School of Government. He was previously a postdoctoral fellow in the NHLBI Cardiovascular Disease Epidemiology Training Program in Behavior, the Environment, and Global Health. He received his PhD in Population Health Sciences (track: Public Health Nutrition) from the Harvard University Graduate School of Arts and Sciences in 2024, and also holds an SM degree in Biostatistics from the Harvard T.H. Chan School of Public Health (2024) and an MS degree in Epidemiology from the University of California, Berkeley (2019). His research focuses on evaluating existing and potential social policies and programs that are poised to reduce cardiometabolic disease, with an emphasis on applying causal inference and simulation-based methods. At the SPHERE Center, Matt examines the impacts of social policies, including paid family leave and local policies implemented during the COVID-19 pandemic, on food insecurity, child and adult nutrition, and cardiometabolic health.

Tom Lindman, PhD, MPP, is a David E. Bell Postdoctoral Fellow at the Harvard Center for Population and Development Studies. He received his PhD in Public Policy and Management from the University of Washington and Master of Public Policy degree from the University of California, Berkeley. He uses causal inference methods to study how U.S. social policy affects family wellbeing, drawing on concepts from social demography, epidemiology, and labor economics. As a Bell Fellow, Tom is studying how policies that provide job flexibility for working parents—such as paid family leave—interact with employment to affect parent and child health.

Chelsea Lodge is an MPH student in Social and Behavioral Sciences at the Harvard T.H. Chan School of Public Health. She holds a BS in Public Health from Stetson University, where she focused on sustainable food systems and community health. Her research interests center on social safety net policies that address food insecurity and diet-related health disparities. Before attending Harvard, Chelsea worked in SNAP-Ed and served in FoodCorps, where she taught children about food and nutrition through school garden programs

Tatyana Olivari, MD, is a clinical Neonatal-Perinatal Medicine fellow and Health Services Research fellow at Harvard. She earned her MD from Emory University, completed pediatric residency at Northwestern University, and will be pursuing an MPH at Harvard T.H. Chan School of Public Health starting summer 2026, along side her clinical and research fellowhips. Her research interests focus on the social determinants of maternal and infant nutrition. 

Taylor J. Robinson, MPH, is a researcher at the SPHERE Center. She is currently a PhD student in Population Health Sciences at the Harvard Chan School of Public Health in the Department of Social and Behavioral Sciences. She is also a T32 in Sleep, Circadian, and Respiratory Neurobiology at Harvard Medical School Division of Sleep Medicine. She earned her MPH from the University of Pittsburgh Graduate School of Public Health in the Department of Epidemiology. She incorporates spatial and social epidemiologic methods and a health equity lens to interrogate the causal and historical relationship between neighborhood and housing conditions and racial health disparities. Her dissertation work focuses on the relationship between sleep and cardiovascular health, wealth, and neighborhood change. Taylor works with the SPHERE Center on evaluating the effects of COVID-19 expansion programs on pregnancy outcomes in the Pregnancy Risk Assessment Monitoring System (PRAMS) dataset.

Valentina Salazar Sandoval, BS, is an MPH student in Health and Social Behavior at Harvard T.H. Chan School of Public Health. She earned her BS in Public Health from the University of Texas at Austin. Prior to Harvard, she worked as a Program Specialist in the Tuberculosis and Hansen’s Disease Unit at the Texas Department of State Health Services, where she focused on policy implementation and program evaluation. Her research interests focus on the effects of social and economic policies on health equity, with a particular emphasis on federal safety-net programs and their impact on immigrant and other high-need populations.

Swathi Srinivasan, MPhil, is a PhD student in Population Health Sciences at Harvard University. Based in the Department of Social and Behavioral Sciences, Swathi is interested in utilizing data and policy to address social and structural inequality and disparities in disease outcomes, particularly among low-income communities. Prior to pursuing her PhD, Swathi received her AB in Social Studies and History of Science at Harvard and an MPhil in History of Science from Oxford. She has also previously worked at the UNAIDS headquarters in Geneva, the White House COVID-19 Health Equity Task Force, and Boston Health Care for the Homeless Program.

Lidya Tadesse, MHS, is a PhD student in Population Health Sciences at Harvard University based in the Department of Social and Behavioral Sciences. She is interested in employing quasi-experimental study designs to evaluate and inform a broad range of health and social policies, including poverty reduction, immigration, and injury prevention. Lidya received her BA in Public Health Studies and MHS in Epidemiology from Johns Hopkins University. Prior to joining Harvard, she worked as a data and policy analyst supporting several federal health agencies.

Marilyn D. Thomas, MPH, PhD, is an assistant professor at the University of California San Francisco. She earned her MPH from San Francisco State University and her PhD in Epidemiology from the University of California, Berkeley, and completed a postdoctoral fellowship in the Departments of Epidemiology & Biostatistics and Psychiatry at UCSF. Her primary interest is to understand how social policies, practices, and norms contribute to racial and socioeconomic health disparities. She has expertise in integrating social theory, measuring exposure to racism, and estimating the intersections of race, socioeconomic position, and socio-environmental factors using statistical interaction and case-only study designs. Her research investigates the role that structural, institutional, and everyday social marginalization plays on disparities in accelerated aging and physiologic dysregulation; police use of fatal force; and how socioeconomic and demographic factors modify these effects. To practice self-care, she likes hiking, dining out, seeing live music/comedy/theater, traveling, and playing guitar.

Guangyi Wang, PhD, is a Research Specialist at UCSF and a Research Associate at the SPHERE Center. She received her PhD in Human Sciences from the Ohio State University. Dr. Wang’s work focuses on policy-based research on family well-being, especially in the areas of health and social policy. During her doctoral training, she used a variety of quasi-experimental designs and survey data to examine the economic and social impacts of the Affordable Care Act and the Earned Income Tax Credit, including homeownership, marriage, and health. At the SPHERE Center, she works on projects examining the effects of school segregation and income support policies on health. Outside of work, she enjoys spending time with her cat and friends, baking, and traveling.

Whitney Wells, PhD, is a social epidemiologist and postdoctoral research fellow at the University of California, San Francisco. She received her PhD in Epidemiology & Translational Science at UCSF. Her research focuses on the health impacts of family support policies, including policies to support access to early childhood education and care. She uses quasi-experimental methods to generate evidence about policies and programs that can support the health of parents and children. In her free time she likes taking on overly ambitious knitting projects and being in nature.

Halim Yoon, PhD, MSW, is a postdoctoral research fellow at the SPHERE Center, based at the Harvard Center for Population and Development Studies (HCPDS). She received her PhD in Public Administration from Syracuse University and her MSW from Seoul National University in South Korea. Her research examines how social policies interact with life-course experiences, socioeconomic conditions, and family relationships—including the exchange of time and financial support—to shape health and well-being in later life. Her doctoral dissertation used applied econometric methods to investigate how reforms to the Social Security retirement age affect health, unemployment, and family caregiving among middle-aged and older adults. As part of the SPHERE Center, she studies the effects of county-level COVID-19 social and economic policies on mental health and healthcare utilization.

Claire D. Brindis, DrPH, is a Distinguished Professor of Pediatrics and Health Policy and Emerita Director of the Philip R. Lee Institute for Health Policy Studies at the University of California San Francisco. As a Latina bi-lingual, bi-cultural researcher, her research experience is in program evaluation and implementation science, as well as policy research on how social determinants impact health. She has brought this distinct perspective to several major formative and impact evaluations and research projects across diverse health care and public health content areas, including adolescent and young adult health at the federal, state, and local levels. Dr. Brindis also has expertise in the translation of research findings into policy and its dissemination to a wide variety of stakeholders. 

Daniel E. Dawes, JD, is a member of the SPHERE Center’s Advisory Board. He serves as senior vice president of global health and founding dean of the School of Global Health at Meharry Medical College. Prior to this, he served as executive director of the Satcher Health Leadership Institute and a professor of health law, policy, and management at Morehouse School of Medicine. He is the author of two groundbreaking health policy books, 150 Years of Obamacare and The Political Determinants of Health. Dawes was instrumental in developing and negotiating the Mental Health Parity Act, the Genetic Information Nondiscrimination Act, the Americans with Disabilities Act Amendments Act, and the Affordable Care Act’s health equity-focused provisions. Dawes is a member of the National Academy of Medicine and a fellow of the New York Academy of Medicine, and he serves as an advisor to The White House COVID-19 Health Equity Task Force and as an appointed member of the CDC’s Advisory Committee to the Director where he co-chairs the CDC’s health equity work. 

David B. Harris, PhD, is a member of the SPHERE Center’s Advisory Board. He is the President of Children’s Research and Education Institute, a partner at Kids Project, a senior research fellow at the Center on Poverty and Social Policy at Columbia University, an affiliate of the Center on Poverty and Inequality at Stanford University, and a senior research fellow at UNICEF Innocenti, Global Office for Research and Foresight.