Dr. Shiel received a bachelor of science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his internal medicine residency and rheumatology fellowship at the University of California, Irvine. He is board-certified in internal medicine and rheumatology. He is a fellow of the American Colleges of Physicians and Rheumatology.
Dr. Shiel is in active practice in the field of rheumatology in south Orange County, California. He is a partner in the Mission Internal Medical Group and is a manager of LLCs for the group.
Dr. Shiel is co-editor-in-chief of the Webster's New World Medical Dictionary, Year 2000 First Edition, Year 2003 Second Edition, and Year 2008 Third Edition. He is proud to have served as chief editor for MedicineNet.com since he co-founded it in 1996. He has authored hundreds of articles for the web site and remains an advisor and chief editor for MedicineNet.com, which was sold to WebMD in 2005.