Dr. Parnell is a board-certified obstetrician-gynecologist in private practice in Dallas, Texas. He is an Associate Clinical Professor of Obstetrics and Gynecology at the University of Texas Southwestern Medical Center in Dallas. He served on the national perinatal safety committee for HCA Healthcare where he co-authored an internet-based fetal monitoring course used to train physicians and nurses nationally. Dr. Parnell is on the Board of Directors of the Texas Healthcare Trustees Association and the Parkland Center for Clinical Innovation. He is the past chairman of the board at the Parkland Health and Hospital System. He also previously served on the Board of Trustees of Medical City Dallas Hospital and of the Dallas County Medical Society. He presently serves on the American Hospital Association’s Governance Committee and the Texas Hospital Association’s Council on Public Policy. Dr. Parnell has a certificate in Nonprofit Governance from the University of Texas at Dallas.