THRO Team: Building Research Partnerships for Healthy Tribal Nations

Karina L. Walters, Ph.D., M.S.W.


Karina L. Walters, Ph.D., M.S.W., an enrolled member of the Choctaw Nation of Oklahoma, is director of the NIH Tribal Health Research Office (THRO). In this role, she leads the THRO team and works to unify NIH representatives, research, and resources to improve the health of American Indians and Alaska Natives. She is deeply committed to engaging Tribal leadership in health research efforts. A social epidemiology and health prevention scholar, Dr. Walters has more than 28 years of Native health research experience, encompassing foundational science, disease prevention, health promotion, and intervention research. Prior to NIH, she was a tenured full professor and the Katherine Hall Chambers Scholar at the University of Washington (UW) School of Social Work. She is also the founding director of the UW Indigenous Wellness Research Institute, and served from 2012-2019 as Associate Dean for Research at the UW School of Social Work. Dr. Walters is the first American Indian fellow inducted into the American Academy of Social Welfare and Social Work. She earned a bachelor’s degree in sociology from the University of California, Los Angeles (UCLA) and an M.S.W. and a Ph.D. in social welfare, also from UCLA. 

Learn more about Dr. Walters.

Sheila Caldwell, Ph.D.

Senior Advisor

Dr. Sheila Caldwell, Mi'kmaq descendant, is senior research advisor in THRO. She provides expert guidance and assistance on major Tribal health research policy issues affecting NIH, the biomedical research enterprise, and American Indian and Alaska Native communities across the country. Dr. Caldwell joined THRO from NIH’s National Institute of General Medical Sciences, where she directed the Native American Research Centers for Health (NARCH) program, as well as components of the Institutional Development Award (IDeA) program. She graduated from George Washington University with a Ph.D. and a M.Phil. in Molecular and Cellular Oncology.

Selina Keryte, M.P.H

Health Science Policy Analyst

Ms. Selina Keryte, a member of Navajo Nation, is a health science policy analyst in THRO. She uses her extensive experience serving American Indians and Alaska Natives to coordinate work with the NIH Tribal Advisory Committee and develop cultural awareness trainings for NIH staff and extramural researchers. Prior to joining NIH in 2020, Ms. Keryte was the national lead for the Domestic Violence Prevention Program at the Indian Health Service and led efforts to strengthen capacity among the 12 nationally recognized Tribal Epidemiology Centers. She has a M.P.H. from the University of New Mexico.

Mayra Medrano

Executive Assistant

Ms. Medrano joined THRO in October 2023 as an executive assistant to provide administrative and organizational support to Dr. Karina Walters and her team. Before joining THRO, Mayra worked for the Rehabilitation Medicine Department at the NIH Clinical Center for three and half years, where she provided administrative support for rehabilitation sciences and services that included budget, procurement, IRB audits, and processed payments for research volunteers. Mayra was part of the Travel Task Force to discuss efficient and effective ways to process travel. She has 15 years of administrative support experience and enjoys volunteering to give back to her community, focusing on youth, including Latinos.

Jacqueline Reardon

Program Specialist

Ms. Jacquelyn (Jackie) Reardon joined THRO in 2020 as a program specialist. She provides administrative and organizational support to help THRO meet its NIH-wide goals for Tribal health research. Previously, Ms. Reardon worked in the NIH Office of AIDS Research, where she assisted with the development and implementation of the Paperless Administrative Support System (PASS), managed the summer intern program, and supervised the scanning team. She graduated from the Academy of Business with a Certification in Information Processing. A leader in her community, Ms. Reardon coaches young people in competitive kickball.

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