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  • Assistant Professor Adjunct

    Research Interests
    • Competency-Based Education
    Dr. Gielissen earned her medical degree at the University of Chicago - Pritzker School of Medicine before completing her Internal Medicine / Pediatrics training at Yale New Haven Hospital. She completed the General Internal Medicine Medical Education Fellowship and an MHS through the Medical Education Pathway (MHS-Med Ed) in 2018. She previously served as the Ambulatory Associate Program Director for the Yale Traditional Internal Medicine Program, Associate Clerkship Director for the Internal Medicine Clerkship, and directed the Yale Pediatrics Clinician-Educator Track (PCET) and Yale Internal Medicine Clinician-Educator Distinction (CED). In 2019, she joined as a co-editor of the Yale Office-Based Medicine (YOBM), an ambulatory curriculum used at over 300 programs across the country. She is currently an adjunct faculty at Yale. Dr. Gielissen's scholarship focuses on Entrustable Professional Activities (EPAs) as a form of assessment in both the Undergraduate and Graduate Medical Education space. She also performs qualitative research on Entrustment Decision-Making and on faculty development to enhance the quality of feedback and evaluation in clinical settings.
  • Assistant Professor; Director of Performance Improvement, Yale School of Medicine; Director of Clinical Reasoning, Yale School of Medicine; Associate, Educator Development in Teaching Clinical Reasoning, Teaching and Learning Center

    Thilan Wijesekera, MD, MHS received his medical degree from the University of Rochester School of Medicine and Dentistry before completing his residency training in Yale University’s Primary Care Residency Program. He subsequently completed a General Internal Medicine Fellowship in Medical Education at Yale University School of Medicine, during which he received a Master of Health Science degree in the Medical Education Pathway.   In 2018, he joined the Academic Hospitalist Program in the Yale Section of General Internal Medicine.  He is active in medical education, particularly at Yale University School of Medicine, where he has roles as the Director of Clinical Reasoning and a section leader in the Interprofessional Longitudinal Clinical Experience. He also has a role in the Teaching and Learning Center as an Associate for Clinical Reasoning Educator Development, where he provides and collaborates on consultations, workshops, and scholarship related to teaching clinical reasoning.   Dr. Wijesekera's educational interests include clinical skills, curriculum development, interprofessional education and mentorship for medical students and residents.  His research interests include clinical reasoning, diagnostic error, and interprofessional education with recent publications in JAMA Internal Medicine, Academic Medicine, and Journal of General Internal Medicine.  He gives faculty development workshops regionally and nationally on teaching clinical reasoning and diagnostic error, on which he completed a fellowship with the Society to Improve Diagnosis in Medicine (2018).