A medical license is required for a doctor to practice medicine in a particular state. Requirements vary by state but most require, at a minimum, post-graduate training in the doctor’s specific specialty. An NPI number is a national identifier unique to an individual health care provider and is managed by the Center for Medicare & Medicaid Services (CMS).
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- Currently 4 of 4 stars
The overall average patient rating of Dr. Thomas O'Brien is Excellent.
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Specialties & Research
Dr. Thomas O'Brien, MD is board certified in Internal Medicine and Gastroenterology.
Education & Awards
Dr. O'Brien graduated from Saint Louis University.
Dr. O'Brien has 3 hospital affiliations:
- California Pacific Medical Center - Davies Campus
- Kaiser Permanente Medical Center San Rafael
- San Rafael Medical Center