Verified 2026 Physician Ranking

Top Gastroenterologists in Oregon, 2026

Published by Palm Beach County Medical Media Group · Last updated May 1, 2026

PBCMMG Excellence Certified \u2014 Recognizing Excellence in Healthcare

How this ranking was built: We applied PBCMMG's seven weighted criteria (board certification, years in active practice, disciplinary record, aggregate patient reviews, hospital affiliations, specialty training, peer recognition) to every gastroenterology physician with active credentialing in Oregon. Sources: NPPES Registry, ABMS, state medical boards, aggregated public review data. Last reviewed May 2026.

  1. #1

    Douglas Walta, MD

    GastroenterologyOregon, OR21+ years in practice

    Douglas Walta, MD, practices gastroenterology in Oregon, OR. NPI-verified active practice since 2005.

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  2. #2

    Atif Zaman, MD

    GastroenterologyOregon, OR20+ years in practice

    Atif Zaman, MD, practices gastroenterology in Oregon, OR. NPI-verified active practice since 2006.

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  3. #3

    Ranjan Mascarenhas, MD

    GastroenterologyOregon, OR20+ years in practice

    Ranjan Mascarenhas, MD, practices gastroenterology in Oregon, OR. NPI-verified active practice since 2006.

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  4. #4

    Donald Yang, MD

    GastroenterologyOregon, OR20+ years in practice

    Donald Yang, MD, practices gastroenterology in Oregon, OR. NPI-verified active practice since 2006.

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  5. #5

    Clifford Carrol, MD

    GastroenterologyPennsylvania, PA20+ years in practice

    Clifford Carrol, MD, practices gastroenterology in Pennsylvania, PA. NPI-verified active practice since 2006.

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  6. #6

    Fouad Otaki, MD

    GastroenterologyOregon, OR16+ years in practice

    Fouad Otaki, MD, practices gastroenterology in Oregon, OR. NPI-verified active practice since 2010.

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  7. #7

    Arnab Mitra, MD

    GastroenterologyOregon, OR14+ years in practice

    Arnab Mitra, MD, practices gastroenterology in Oregon, OR. NPI-verified active practice since 2012.

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  8. #8

    Jonathan Hattenhauer, DO

    GastroenterologyCalifornia, CA11+ years in practice

    Jonathan Hattenhauer, DO, practices gastroenterology in California, CA. NPI-verified active practice since 2015.

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