Gastroenterology & GI Lab | St. Jude Heritage Medical Group
Gastroenterology • Fullerton, CA
Clinic Type
Gastroenterology
Address
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Phone
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Opening Hours
Not published — contact the clinic to confirm hours.
Services Offered
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Insurance & Payment
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Languages Spoken
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What Patients Say
Overall sentiment across review platforms: mixed
- St. Jude Heritage Medical Group Provider Profile (Dr. Patrick T. Koo): 4.7 out of 5 stars (154 ratings) (154)
- St. Jude Heritage Medical Group Provider Profile (Dr. Sajen John Mathews): 4.9 out of 5 stars (173 ratings) (173)
- St. Jude Heritage Medical Group Provider Profile (Jill Olmstead, NPC): 4.9 out of 5 stars (222 ratings) (222)
- Birdeye (St. Jude Digestive Health at Knott Family Endoscopy Center): 4.5 out of 5 stars (18)
Patients praise
- Highly praised physicians for being kind, caring, and thorough
- Professional and compassionate staff interactions in many instances
- Efficient clinical processes and well-run endoscopy procedures
- Helpful and attentive bedside manner that makes patients feel comfortable
Common complaints
- Difficulty scheduling appointments and long hold times on the phone
- Concerns regarding administrative/office communication and follow-up directions
- Occasional negative patient interactions with specific providers or staff members
- Reports of perceived lack of thorough examination or limited telehealth-only consultations in some instances
"OMG, I was on hold for 45 minutes... Finally after 45 minutes I reached Jennifer and all she said was Dr. Yoon has to call me back maybe next Tuesday (this is Friday). This is just unacceptable."
— Patient review on LocalityBiz"Jill always goes above & beyond the call of duty for me! Suggesting health recipes, exercises anything to help me & not only my GI Health but my all over health."
— Patient review on St. Jude Heritage Medical Group provider profile"Dr. Matthew's is so kind and caring. He always listens to me as I share my concerns and tries to give me answers I can easily understand. I am so thankful to have him as part of my care team."
— Patient review on St. Jude Heritage Medical Group provider profileSynthesized from public review platforms as of Jul 10, 2026 — sources: [1][2][3][4].
In the News
- Dr. Wanjun S. Bae, MD - Gastroenterologist in Fullerton, CA — May 14, 2026
- Janet Servoss — Jun 24, 2026
- Fullerton firefighters get an extra eye on their esophagus — Jul 24, 2025
- Providence St. Jude Medical Center to Host Free Esophageal Cancer Screening for Fullerton Fire Department on July 23 - Fullerton Observer — Jul 20, 2025
- UnitedHealthcare and St. Jude Contract Termination in 2026: What Fullerton Seniors Need to Know - Skyline Benefit — Nov 5, 2025
Information sourced from the clinic's website as of July 10, 2026.
More gastroenterology clinics in Fullerton
St. Jude Heritage Fullerton (St. Jude Medical Center) is a nonprofit, Magnet-accredited tertiary care hospital in Fullerton, California (founded 1957). It offers comprehensive gastroenterology services as part of a broader 320-bed facility serving Orange County, with advanced diagnostics and specialized care in cardiology, oncology, neurology, orthopedics, digestion, and rehabilitation. Location: 101 E Valencia Mesa Dr, Fullerton, CA 92835. Contact: 714-871-3280. Owned and operated within Providence St. Jude Medical Center (private, not-for-profit).
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