What is John Roark's NPI number?

John Roark's National Provider Identifier (NPI) is 1609834266, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.

What is John Roark's specialty?

John Roark is listed in the NPPES registry with a primary specialty of Gastroenterology Physician (Allopathic & Osteopathic Physicians).

Where is John Roark located?

John Roark's practice location on file with NPPES is 3741 Linwood Ave, Oakland, CA 94602-1711.

What is John Roark's phone number?

The practice phone number listed in the NPPES registry for John Roark is (510) 589-8774.

Is John Roark's NPI active?

Yes — John Roark's NPI (1609834266) is active in the NPPES registry as of the last update on 2026-02-10.

IndividualActive

John Roark, MD

NPI 1609834266 · Gastroenterology Physician · Oakland, CA

John Roark, MD is a Gastroenterology Physician provider in Oakland, CA (NPI 1609834266).

Provider details

NPI number: 1609834266
Entity type: Individual
Primary specialty: Gastroenterology PhysicianAllopathic & Osteopathic Physicians
Credential: MD
Sex: Male
Sole proprietor: No
License: G038581 (CA)

Specialties & taxonomies

Gastroenterology PhysicianPrimary207RG0100XLicense G038581 (CA)
Allopathic & Osteopathic Physicians

Profile Score

Detailed profile(91/100 index)

A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.

Registry tenure38% of score
20 yrs in NPPES registry
Profile completeness38% of score
100% of core fields populated
Practice footprint23% of score
1 documented practice location

Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.

Practice location

3741 Linwood Ave

Oakland, CA 94602-1711

Phone: (510) 589-8774

Street-level locationGet directions

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Mailing address