John Sparrow Duffy MD

The following disclaimer is related to board certifications obtained from ABMS®, denoted by the ABMS® logo.

This information is proprietary data maintained in a copyrighted database owned by the American Board of Medical Specialties®. The display and presence of ABMS Data in no way constitutes any affiliation, association with, or endorsement of any advertising, promotion, or sponsorship by ABMS and its affiliates and subsidiaries, the ABMS Member Boards, or ABMS board certified physicians and medical specialists. Copyright 2025 American Board of Medical Specialties®. All rights reserved.

The user is responsible for ensuring that the profile obtained in this directory is the profile of the physician or medical specialist being sought.

A self-designated specialty, subspecialty, or practice area neither implies nor is equivalent to ABMS board certification or the existence of specialized training by or competence of a physician or medical specialist.