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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The overall average patient rating of Dr. John O'Brien is Excellent.
Specialties & Research
Dr. John O'Brien, MD is board certified in Internal Medicine.
Education & Awards
Dr. O'Brien graduated from Rosalind Franklin University, North Chicago.
Dr. O'Brien has 2 hospital affiliations:
- Advocate Illinois Masonic Medical Center
- John H. Stroger,Jr.,Hospital of Cook County
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- Additional Information
- Dr. John Martin O'Brien MD is a male Internist, has 23 years of experience and practices in Internal Medicine and Adolescent Medicine.
- Where does Dr. John M. O'Brien practice?
- Dr. John O'Brien has 2 office locations.
Dr. John O'Brien practices Internal Medicine and Adolescent Medicine near Chicago, IL.
See Chicago Internists and Chicago Adolescent Specialists.