T32 Training Program Trainees and Faculty

Zhang Zhang, Ph.D., MSc, is a post-doctoral fellow appointed jointly in the Health Services and Outcomes Research in Aging Populations T32 program and the Hopkins Business of Health Initiative (HBHI). Her current research focuses on technology innovation (e.g. digital health and health information systems) and policies to improve health service delivery and outcome for complex health conditions. She is also interested in life-course aging, long-term care and integrated care for older adults. Her expertise concentrates on causal inference methods in quantitative modeling, and applied economics approaches for randomized (RCT) and non-randomized (quasi-experimental) designs in the evaluation of policy and clinical interventions. She received her Ph.D. in Health Economics from the University of North Carolina at Chapel Hill and was predoctoral trainee at Carolina Population Center.  She earned her MSc in Health policy, Planning, and Financing from the London School of Economics (LSE) & London School of Hygiene and Tropical Medicine (LSHTM). Her research and work experience includes designing interventions, policies, and strategies for long-term care systems and service delivery at the World Bank Group and the World Health Organization. 

Sarah Jabour, MD holds a B.A. in Public Health and International Studies with a minor in Social Policy from Johns Hopkins University and an M.D. from the University of Michigan. She joined as a postdoctoral fellow on the Health Services and Outcomes Research in Aging Populations T32 Training Program after completing her second year of general surgery residency at Johns Hopkins. During her academic development time, she will pursue a PhD in Clinical Investigation through the Graduate Training Program in Clinical Investigation (GTPCI) at the Johns Hopkins Bloomberg School of Public Health. She is passionate about integrating frailty assessments and interventions into surgical care with a particular emphasis on quality of life outcomes and the role of the social determinants of health. She is also looking forward to learning about implementation science at the health systems level to address the surgical needs and peri-operative risks of aging and frail patients. 

Laura Brotzman, PhD was appointed to the Health Services and Outcomes Research for Aging Populations T32 Training Program in August 2025 as a postdoctoral fellow in the Johns Hopkins School of Medicine, Division of Geriatric Medicine and Gerontology. Laura holds a BA in English and Sociology from Lafayette College, an MPH in Sociomedical Science from Columbia University, and a PhD in Public Health from University of Michigan. Her research focuses on understanding older adult and clinician medical decision making, risk communication, and implementation of clinical practice guidelines. She uses mixed-methods and mental models methodologies to investigate how older adults understand risk/benefit tradeoffs, evaluate clinical information, and make decisions about preventive and other care services (such as cancer screening and medications), especially in the context of limited or declining life expectancy. Her research seeks to improve broader health service outcomes by improving how older adults engage in and make medical decisions. 

John Mulcahy, PhD was appointed to the Health Services and Outcomes Research for Aging Populations T32 Training Program in August 2025 as a postdoctoral fellow in the Department of Health Policy and Management. John received a BS in biology with a minor in public health from the University of Minnesota, a MSPH in health policy from the Johns Hopkins Bloomberg School of Public Health, and a PhD in health services research, policy, and administration from the University of Minnesota School of Public Health. Between his master’s and doctoral studies, John worked as a data analyst for the National Health and Aging Trends Study where he researched the link between unpaid caregivers and the long-term care outcomes of the older adults they care for. John has experience using a variety of linked data sources including health insurance claims, survey data, and electronic health records to answer quasi-experimental research questions. His research interests focus on how our healthcare system can incentivize providers to recognize and help address the functional and social needs of their older patients, particularly in the case of patients living with Alzheimer’s disease and related dementias. 

Alexa Bragg is a third-year Health and Services Research and Policy PhD candidate in the Department of Health Policy and Management at the Johns Hopkins Bloomberg School of Public Health. Alexa’s research interests include the organizational behavior of nonprofit and for-profit long-term care institutions, as well as the evolving role of alternative care delivery models in home health. Alexa received her MPH and MBA from Boston University in 2023. Prior to pursuing her doctoral degree, Alexa served as an Associate Health Transformation Analyst for MITRE’s VA Enterprise & Healthcare Operations Transformation Department. In addition, Alexa supported ongoing socio-behavioral and health service research projects at Boston Medical Center for the Department of Family Medicine.

Davoodi is a third-year Health and Services Research and Policy PhD candidate in the Department of Health Policy and Management. She holds a Bachelor of Science in Physiology and Neuroscience from the University of California, San Diego, and a Master of Public Health from the Brown University School of Public Health. Prior to coming to Hopkins, she was a Senior Data Analyst at the Center for Gerontology and Healthcare Research within the Brown University School of Public Health leveraging claims data to assess policy questions specific to End-stage renal disease. She also worked as an Emergency Medical Technician throughout the COVID-19 pandemic. Davoodi’s research interests include examining policies and programs pertaining to the health care older adults in the United States, specifically in the areas of financing, delivery, spending, organization, and health outcomes.

Yiting Li is a first-year doctoral student in Health Services Research and Policy in the Department of Health Policy and Management at the Johns Hopkins Bloomberg School of Public Health. Her research interests include aging and kidney disease, with a focus on dementia and delirium among older adults with end-stage kidney disease (ESKD). Yiting earned her MPH from the University of Michigan in 2012. Prior to beginning her doctoral studies, she accumulated over 10 years of experience as a data analyst. She worked in the Quality and Safety Department at Trinity Health System and was most recently appointed Assistant Research Scientist at NYU Langone Health. She has extensive experience working with claims data (including Medicare, Medicaid, and Optum Clinformatics), electronic health records, and national registries (including United States Renal Data System, Scientific Registry of Transplant Recipients) to study the intersection of aging and kidney disease, particularly in the context of ESKD and transplantation.