Dr. Stephenson is a Professor at the University of Toronto, and Section Head of Cardiac Electrophysiology at The Hospital for Sick Children (SickKids). Her undergraduate degree was done at Mount Holyoke College, where she graduated with Honors in Biology and High Honors in Philosophy with a focus on medical ethics in the paediatric population. She received her MD from Columbia University, College of Physicians and Surgeons, and her M.Sc. in Clinical Epidemiology from the University of Toronto.
Her paediatric residency, cardiology fellowship, and electrophysiology fellowship were all done at Children’s Hospital, Boston. Dr. Stephenson’s research work in electrophysiology has focused on clinical investigations, centered on several topics in the field of electrophysiology and heart function, particularly as related to paediatric use of pacemakers, cardiac resynchronization therapy, and implantable cardioverter defibrillators. She was the Chair of the SickKids Research Ethics Board from 2015 to 2025. She helped to develop the SickKids AI research evaluation framework, started the SickKids AI dedicated REB, and has done research regarding research ethics, AI, and youth.