Clinical Leadership

As Chief Medical Officer and co-founder of VillageMD and an esteemed practicing physician, Dr. Fields is transforming the way patients and physicians experience health care. In the early 1990s, prior to beginning VillageMD, Fields initiated and served as president of Village Family Practice, which became one of the largest primary care groups in Houston and was recognized for its quality of care by the Centers for Medicare and Medicaid Services (CMS) and the National Committee for Quality Assurance (NCQA). An avid golfer and reader who enjoys family time with his wife and 3 children, Fields was named to Modern Healthcare’s 2020 List of the 50 Most Influential Clinical Executives.

Dr. Barrison is the Chief Physician Executive at Summit Health. He has held several leadership positions since joining the organization in 2001. Dr. Barrison was previously a member of the Summit Medical Group Board of Directors, where he served as Vice Chair, and most recently was a member of the Summit Health and CityMD Board of Directors. In his current role, his focus centers around the management of Summit Health’s 2,800+ clinical providers and its population health-related programs. Dr. Barrison received his undergraduate degree from Columbia University and his medical degree from New York University Grossman School of Medicine. He is a board-certified gastroenterologist. 

Jack V. Cappitelli, MD, has served as Chief Medical Officer, New Jersey Region, at Summit Health since 2020, and before that he was Regional Medical Director for Northern New Jersey. Prior to joining Summit Health in 2017, Dr. Cappitelli served for 14 years as President and Managing Partner at New Jersey Associates in Medicine, where he practiced as a board-certified internal medicine physician since 1998.
 
After completing his undergraduate education at Rutgers University, Dr. Cappitelli earned his Doctorate in Medicine from the University of Medicine and Dentistry of New Jersey Medical School. He received his Internal Medicine Training at the University of Medicine and Dentistry-Robert Wood Johnson Medical School, where he also earned the honor to serve as Chief Medical Resident and received an Outstanding Teaching Award.

Dr. Calayag is Chief Medical Officer for Summit Health’s NY North and Connecticut regions. She is board-certified in obstetrics and gynecology and is a Fellow of the American College of Obstetrics and Gynecology.

Dr. Calayag’s scope of practice includes general obstetrics and gynecology, both high- and low-risk pregnancies, with special interest in fertility, laparoscopy, and minimally invasive surgery. She sees patients from adolescence through menopausal years.

Dr. Calayag has served in leadership positions at Westmed Medical Group, a Summit Health company, since 2014, when she was Chair of the Women’s Health Department and pioneered initiatives for safe reduction of the primary cesarean section, depression screening and treatment, and raised awareness of domestic violence among our patients. She was named Deputy Medical Director of Westmed in 2018 and Chief Medical Officer in 2021. She played a critical role in solidifying the group’s partnership with Summit Health-CityMD and has subsequently supported the recent acquisition by VillageMD.

Dr. Calayag attended Wesleyan University in Connecticut for undergraduate studies and graduated with university honors. She earned her medical degree from SUNY Stony Brook School of Medicine in New York and completed her residency training at Harvard University School of Medicine’s Beth Israel Hospital in Boston, MA, where she was also a clinical teaching fellow for Harvard medical students.

Dr. Thomas Cornwell, MD, has made home-based primary care the focus of his esteemed medical career, and he continues that emphasis as our National Medical Director for Village Medical at Home. Besides providing care for literally thousands of homebound patients, he has mentored hundreds of physicians, medical students, residents, nurse practitioners and physician assistants to spread the word of how beneficial, cost-effective and compassionate home-based care can be.

His innovative care has received recognition including “House Call Doctor of the Year” from the American Academy of Home Care Medicine and the “Pride in the Profession” from the American Medical Association. He is a past president of the American Academy of Home Care Medicine, and a founder of the Home Centered Care Institute, a national organization dedicated to expanding in-home care.

Board-certified physician and Market Chief Medical Officer for Village Medical Arizona, Dr. Karen Wetherell is passionate about changing the way healthcare is delivered in this country to ensure higher quality care and improved outcomes for patients while supporting the providers who are delivering the care.

Prior to her current role with Village, Dr. Wetherell provided medical care as an internal medicine physician for over two decades while serving in many leadership roles along the way including Department Chair and Senior Medical Director positions.

Outside of work, she reenergizes by spending time with her family, exercising daily, and traveling.

David Hatfield, D.O., is Chief Physician Executive of Village Medical. With more than 25 years of experience as a practicing primary care physician, Dr. Hatfield is committed to value-based, preventative care. He believes in helping keep patients healthy and helping those who have illness reach their best outcomes. With his leadership, Village Medical physicians and advance practice providers (APPs) support their patients in managing their chronic conditions while increasing access to high-quality care. He completed his medical training from Kirksville College of Osteopathic Medicine and his undergrad at Arizona State University. He also earned his Master of Medical Management (MMM) from the University of Southern California – Marshall School of Business.

Chris Hyer, PA-C, MPAS, is a skilled physician assistant and leader with a passion for caring for the underserved and a commitment to making healthcare better, more accessible, and more affordable. As Vice President, Advanced Practice Providers at VillageMD, Chris provides strategic and operational leadership for the Village team of nurse practitioners and physician assistants.

He previously held leadership positions as Executive Director for Advanced Practice Providers at Intermountain Healthcare and Medical Director for the Community Health Centers, Inc. (CHC) in Salt Lake City.

Chris attended the University of California Los Angeles' Healthcare Executive Program and obtained his Master's in Physician Assistant Studies from the University of Utah and his Bachelor of Arts in Spanish and Literature, also from the University of Utah.

Dr. Massine is Chief Physician Executive at Summit Health in Bend, OR. He came to Summit Health in 2007 from Oregon Health & Science University in Portland, OR, where he completed a Fellowship in Nephrology. Before fellowship, Dr. Massine served in the United States Air Force, practicing Internal Medicine and teaching residents at Keesler Medical Center at Keesler Air Force Base, Mississippi. In Bend, he has practiced clinical nephrology at Summit Health and previously served as the Chief of Medicine and President of the Medical Staff at St. Charles Medical Center Bend. 

Dr. Massine completed his residency in Internal Medicine at Wright-Patterson Medical Center at Wright-Patterson Air Force Base, OH, in 2001.  He received his medical degree from Oregon Health & Science University and his Bachelor of Science from the University of Oregon. Dr. Massine’s certifications include Hyperbaric Oxygen Therapy training, completed with the International ATMO at the Nix Hospital in San Antonio, TX.  Dr. Massine is board-certified in Nephrology and Internal Medicine. He believes in building long-term relationships with patients while striving to better their health and quality of life.

For more than 20 years, Ravi Mehan, D.O., F.A.C.O.I. has worked as both a clinical executive and a board-certified internal medicine physician. At VillageMD, Dr. Mehan focuses on helping Village Medical clinicians across the southeast region offer personal, coordinated, patient-centered primary care that delivers improved health outcomes. Prior to joining VillageMD, Dr. Mehan spent seven years at WellMed Medical Management as a Florida regional medical director. Dr. Mehan also practiced primary care for 20 years at his own private practice and spent more than 10 years as a physician leader for PCA Hospitalists. During his career, Dr. Mehan built and led programs around care management, utilization management, and clinical and quality management. Dr. Mehan graduated from Nova Southeastern University with a Doctor of Osteopathic Medicine degree, and is board certified in internal medicine from Michigan State University. He received a hospitalist leadership certification from University of California San Francisco.