Clinical Engagement Team

Get to know our team
Senior clinical leadership

Dr. Jen Brull

SVP Clinical Engagement

Dr. Jen Brull is a family medicine physician, who lives in Plainville, Kansas. She obtained her medical degree from the University of Kansas School of Medicine and completed family medicine residency training in Topeka, Kansas. She practiced rural full-scope family medicine for 22 years before transitioning full time to Aledade’s Vice President of Clinical Engagement. She served two years (2013-2014) as an HIT Fellow for the Office of the National Coordinator and was recognized as a Hypertension Control Challenge Champion by the CDC in 2014. She was named as a Top 25 Innovator by Modern Healthcare in 2019 and is a physician leader in performance improvement and change management. Her special interests include integrating promotion of healthy behaviors into the office visit and the use of social media in medicine.

Dr. Lelin Chao

Senior Medical Director

Lelin Chao, M.D. (she/her) is a proud family physician and member of Aledade’s physician leadership team as a senior medical director. After completing her residency in family medicine and community health at Duke University, she pursued a calling for providing care to underserved and marginalized communities in federally qualified health centers in Wilmington, North Carolina and later Baltimore. Interested in health care costs, quality and primary care physician representation in health systems, she joined Amerigroup, Anthem’s Medicaid-managed care program as a medical director. She served on the Board of the National Alliance for School-Based Health Centers as an officer for several years and currently serves as a physician lead for a program on accu-detox for patients in recovery. Her additional interests include delivery innovations to improve care of complex populations, physician leadership, quality improvement applications in value-based care and primary care workforce development.

Dr. Becky Jaffe

Senior Medical Director

Rebecca (Becky) Jaffe, M.D. is a board-certified family physician with more than 30 years of field experience. Her passion, which began with her work at a Community Health Center, was strengthened by teaching at a family medicine residency. Dr. Jaffe has successfully run her own private family practice and has served on the National Board of Directors of the American Academy of Family Physicians as well as the American Medical Society for Sports Medicine. Her leadership on the American Academy of Family Physicians Foundation showcases her strong desire to support primary care. She has served her community as a member of her local hospital board and in various fundraising events. Dr. Jaffe's passion is in supporting independent practice — the safety net of health care. She earned her master's in public health at Drexel University in Philadelphia, Pennsylvania.

Dr. Ryan Knopp

Senior Medical Director

Dr. Ryan Knopp joined Aledade as part-time regional medical director in January 2021. Prior to this role, he served as local medical director for the Kansas/Oklahoma market from 2019-2021. Dr. Knopp remains a partner and practicing physician with Stonecreek Family Physicians in Manhattan, Kansas. His practice has been with Aledade since 2017.

Dr. Sarah Mullins

Senior Medical Director

Dr. Sarah Mullins trained at Duke University, University of Maryland Medical School and served as chief resident at Christiana Care Family Medicine Residency. She is a practicing family physician and owner of Stoney Batter Family Medicine in Wilmington, Delaware. Her practice joined Aledade in 2014, and participates in value-based contracts through Aledade for Medicaid, commercial insurance as well as Medicare and Medicare Advantage. Dr. Mullins is the regional medical director for Delaware, Maryland and Washington D.C., encompassing the three ACOs and the MDPCP Care Transformation Organization in these areas. She has served as a national speaker for the AAFP on tobacco cessation education, multiple pharmaceutical migraine therapies, the Dravet Syndrome Foundation and the Epilepsy Foundation of Delaware, Pennsylvania Medical Marijuana certification course and multiple residency program business topics.

Dr. Shawn Purifoy

Senior Medical Director

Dr. Shawn Purifoy has practiced medicine in Malvern, Arkansas for 25 years. He joined the Aledade Primary Care ACO in the fall of 2014, and became the local medical director for the Arkansas ACO in 2017. Dr. Puifoy now serves as the senior medical director while continuing to practice medicine on a daily basis.

Regional medical directors

Dr. Deb Dittberner

Regional Medical Directort

Dr. Deb Dittberner, M.D, MBA is a veteran family physician that trained at the University of Minnesota and served as chief resident at University of Minnesota, Fairview. She acquired her MBA from the University of Texas. She joined Aledade as a regional director for North Carolina after serving as a chief medical officer of a multi-site, multi-specialty clinic and health system in rural Minnesota. She is passionate about innovative models of health care that are evidence-based, patient-centered, team-delivered and focused on the Quadruple Aim.

Dr. Beverly Jordan

Regional Medical Director

Dr. Beverly Jordan is a board-certified family physician in Enterprise, Alabama with over 20 years of experience. She graduated from The University of Alabama School of Medicine and completed her residency at the Tuscaloosa Family Medicine Residency Program as well as a Primary Care Sports Medicine Fellowship at the American Sports Medicine Institute. She currently serves on the Alabama Board of Medical Examiners as well as the board of her local hospital and is a past president of the Alabama Academy of Family Physicians. She has a passion for rural health care and has served as a regional medical director since 2022 while remaining an active managing partner of her private practice which has been with Aledade since 2020.

Dr. Darrin Menard

Regional Medical Director

Dr. Darrin Menard is an independent family practice physician and owner at Scott Family Physicians in Scott, Louisiana. He graduated from Louisiana State University Medical Center in Shreveport and as chief resident from the LSU Medical Center in Lafayette residency program in Family Medicine. He started his solo practice in 1998 and has subsequently grown to five providers in the practice. He achieved recognition as a Fellow of the American Academy of Family Physicians in 2009 and started investigating value-based care by reading articles through the AAFP website. During that education process, he noticed that the most successful ACOs in the country were independent primary care physician-based and his group subsequently joined Aledade at that time as the first practice in Louisiana. Dr. Menard served as local medical director for Louisiana from 2015 to 2021 and is now currently the regional medical director for all of Louisiana practices. He continues to practice medicine and strongly advocates for the health and well-being of his patients throughout the Lafayette Parish region.

Dr. Maureen Padden

Regional Medical Director

Maureen (Mo) Padden, M.D. is board certified in family medicine/obesity medicine, holds a master’s in public health with an emphasis on health education and has extensive experience in graduate medical education and executive medicine. After 29 years of service, she retired from the United States Navy and now practices as a family physician in the Pensacola, Florida community. She joined Aledade as the regional medical director for the Florida/South Carolina market and continues to practice part-time.

Dr. Tim Poulton

Regional Medical Director

As a family medicine physician from Asheville, North Carolina, Timothy Poulton, M.D. is dedicated to delivering high-quality, patient-centered family medicine to ensure all patients receive the best possible care. He obtained his medical degree from the University of Michigan Medical School. His passion for value-based care led him to Aledade, where he enjoys being a part of the dynamic, multi-disciplinary teams that empower independent primary care offices to provide outstanding care for their patients. Dr. Poulton also enjoys working with the Institute for Healthcare Excellence as a faculty member. As a part of the IHE team, he helps bring programs to offices, hospitals and health systems that enhance and transform culture and facilitate strong, interpersonal connections between providers, patients and the health care team members. Dr. Poulton has a special affinity and ease for teaching and puts these skills to work educating providers on HCC and risk capture, in addition to other value-based care concepts.

Dr. Scott Nass

Regional Medical Director

Dr. Scott Nass is a board-certified family physician born and raised in eastern Kentucky. He recently put down roots in northern California after many years in southern California where he completed medical school at Charles R. Drew University School of Medicine and the David Geffen School of Medicine at UCLA. He then completed his residency at Ventura County Medical Center. Nass has been a full-time hospitalist, practiced primary care in a CHC, served as a residency program director and provided telemedicine services as regional medical director for a healthcare start-up. He is a Senior Atlantic Fellow for Health Equity and past president of GLMA: Health Professionals Advancing LGBTQ+ Equality and he is credentialed as a HIV Specialist™ by the American Academy of HIV Medicine.

Dr. Marie Elizabeth-Ramas

Regional Medical Director

Dr. Marie-Elizabeth Ramas is a family physician activist with over a decade of experience practicing full scope family medicine with obstetrics in both rural and urban settings. She joined Aledade in 2021 as regional medical director for New Jersey, New York, New England and North Carolina CHC markets. Dr. Ramas is an avid advocate for high-quality, affordable care for all, focusing on how disparities interface between the patient wellness experience and public health. She began her career in organized medicine as the New Physician member on the National Board of Directors of the American Academy of Family Physicians 2015, and currently serves as president-elect of the New Hampshire Academy of Family Physicians. Through partnership, trust-building and strategic guidance, she commits to creating a safe space where peer-to-peer accountability can promote excellence in performance, patient care and practice culture. In addition to her role in Aledade, she serves on the AAFP Commission of Health of the Public and Science, the Secretary’s Advisory Committee on Infant and Maternal Mortality with the U.S. Department of Health & Human Services and is a regular contributor to both local and national media outlets.

Dr. Catherine Smitas

Regional Medical Director

Dr. Catherine Smitas graduated from Harvard University where she studied History of Science. She attended medical school at The University of Rochester and completed her internal medicine residency at Brown. Upon graduation, she joined the teaching faculty. She and her husband eventually moved back to their hometown near Albany, New York where she joined a private practice. Over the next decade and a half, she helped shepard her practice to success in PCMH, CPCI, CPCI+ and other value-based contracts. She is passionate about the preservation of independent primary care and enjoys guiding practices along the value-based care journey.

Dr. Tanya Stewart

Regional Medical Director

Tanya L. Stewart, M.D., MBA, FAAHPM, is founder and principal consultant with i2We, offering fractional chief medical officer services to employer groups, health care startups and community organizations working to transform the health care system. Previously, Dr. Stewart was the chief clinical transformation officer at UnitedHealthcare, a primary care physician at Northwest Permanente and the hospice medical director at Adventist. She brings a wealth of knowledge and experience in the areas of internal medicine; hospice and palliative care; long-term care; elder care; lifestyle medicine; socio-economic determinants affecting employment and health; clinical program innovation, development and operations; revenue accuracy; affordability initiatives; and physician outreach and engagement. She strives to bring a compassionate heart to the business of medicine. Nationally, she served as a founding member and exam committee chair of the Hospice Medical Director Certification Board and has served on or acted as chair of several committees for the American Academy of Hospice and Palliative Medicine. She received her bachelor’s degree with honors from the University of San Diego majoring in religious studies and biology and minoring in chemistry. She received her medical degree from Tufts University in Boston and her master’s degree in business administration from Oregon Health & Sciences University, Portland State School of Business. When not at work, Dr. Stewart enjoys spending time at her home in the Pacific Northwest with her husband and two children.

Dr. Nita Walker

Regional Medical Director

Dr. Nita Walker is a general internist who practiced internal medicine in Cincinnati, Ohio for 30 years. She obtained her medical degree from the Medical College of Georgia and completed her internal medicine residency at the University of Cincinnati where she also served as chief medical resident. While maintaining a busy medical practice caring for patients with multiple complex conditions, she served as a physician leader for the UC Health Primary Care Network and Ambulatory Services. In these roles, she worked to improve access, operational processes and patient experience. At UC Health she was a champion for value-based care, supporting practices with participation in Comprehensive Primary Care Plus, Transforming Clinical Practice Initiative and other related programs. In addition, Dr. Walker taught graduate trainees and medical students as a clinical faculty member for 30 years. She is currently Professor Emerita in the University of Cincinnati Department of Internal Medicine. She is board certified in internal medicine and a Fellow of the American College of Physicians. She is excited to work for Aledade and support high-quality primary care delivery that allows physicians to enjoy the practice of medicine.