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Research Associate

Dr. Bonnielin Swenor is an Associate Professor at the Johns Hopkins School of Nursing and holds joint faculty appointments at the Wilmer Eye Institute at Johns Hopkins School of Medicine and in the Department of Epidemiology at the Johns Hopkins Bloomberg School of Public health. She is the founder and director of the Johns Hopkins Disability Health Research Center, which addresses health inequities for people with disabilities through research, education, and policy. Dr. Swenor’s career is motivated by her personal experience with vision impairment and focuses on three overlapping areas: (1) finding strategies to maximize health and advance health equity for people with disabilities, (2) addressing healthcare disparities for the disability community; and (3) ensuring people with disabilities have equitable access to higher education and  research careers.

Dr. Varshini Varadaraj, MD, MPH, is a research associate at the Johns Hopkins Disability Health Center.  Trained in clinical ophthalmology, epidemiology and biostatistics, her research goals aim to improve the health of older adults with disabilities, with a focus on vision loss, using a data-driven approach. Her research focuses on examining disparities in health and health care access for people with disabilities, and her prior work has broadly concentrated on two interrelated areas: aging with vision loss and access to care.


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Dr. Nicholas Reed, AuD, is an Assistant Professor in the Department of Epidemiology at Johns Hopkins Bloomberg School of Public Health with a joint appointment in the Department of Otolaryngology-Head and Neck Surgery at Johns Hopkins School of Medicine. He is the director of the Audiology Core at the Cochlear Center for Hearing and Public Health that focuses on integrating measures of hearing into large cohort studies. His research has focused on examining the relationship between age-related hearing loss and health care outcomes, utilization, quality, and spending and utilizing implementation science methodology to create sustainable approaches to addressing hearing loss in the health care system. Dr. Reed collaborates with Dr. Swenor and other faculty of the Disability Health Research Center on improving the inclusion of disability measures in large cohort studies and clinical trials as well as studying access and accommodations for disability in the health care system and using a multi-discipline approach to create sustainable solutions. Lastly, Dr. Reed has a personal interest in improving the understanding of allyship among health care professionals and the responsibilities and limitations that come with playing a supporting role to disabled leaders. 

Dr. Jennifer Deal, PhD, is an epidemiologist and gerontologist with expertise in cognitive aging. She is an assistant professor in the Departments of Epidemiology at the Johns Hopkins Bloomberg School of Public Health and Otolaryngology-Head and Neck Surgery at the Johns Hopkins University School of Medicine. Trained in the epidemiology of aging, Deal studies the effects of hearing loss on an aging brain and how hearing loss influences cognitive function to inform strategies for the primary prevention of cognitive decline and dementia in older adults.


Laura Samuel is an Assistant Professor at the Johns Hopkins University School of Nursing. Her interest in investigating income-based health disparities stems from both her experience helping families meet their basic needs as a primary care nurse practitioner and her childhood experience of financial strain. She now seeks to advance health equity for low-income individuals and families through two related streams of research. First, she has built a body of evidence demonstrating that financial strain contributes to aging-related health disparities and that housing conditions, such as disorder in the home, partly account for socioeconomic disparities. Second, she evaluates the health impact of programs and policies that are intended to improve economic well-being for low-income households. This research has shown that greater participation in the Supplemental Nutrition Assistance Program and higher benefit amounts are associated with improved health outcomes for low-income adults. Her research has been funded by the National Institutes of Health and the Robert Wood Johnson Foundation.



Caroline Cerilli is a Research Program Coordinator for the Disability Health Research Center. Previously, Caroline was a student researcher for the DHRC where she completed her undergraduate thesis on national undergraduate disability inclusion in 2022.

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Prateek Gajwani is a Research Manager at the Disability Health Research Center and at the Wilmer Eye Institute. Prateek is a certified clinical research professional. He completed his MS degree program at Johns Hopkins in 2011 and started working for nuclear medicine and cancer clinical research at Johns Hopkins Medicine. From his graduate school education and working in Public Health and Clinical Research for years, he brings expertise in recruitment strategies, study design, clinical trial management, and regulatory compliance at sites. Prateek operationalizes research and programmatic components of the Disability Health Research Center, collaborates with stakeholders and research partners, and manages research staff efforts.

Current Students

Dr. Erica Twardzik, PhD, is a postdoctoral fellow within the Johns Hopkins Bloomberg School of Public Health, Department of Epidemiology. As a social epidemiologist, Dr. Twardzik’s research investigates the impact of neighborhood-built environments on participation and health. Dr. Twardzik collaborates with members of the Disability Health Research Center to evaluate and describe the accessibility of public transportation systems within the United States.

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Jessica Campanile, medical student at the University of Pennsylvania.

Former Students

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Sabrina Epstein

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Anna Moyer