Gregory Clark, M.D.
NPI 1225141823 · Sleep Medicine (Psychiatry & Neurology) Physician · Portland, OR
Enrolled with Medicare as Practitioner - Neurology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Gregory Clark, M.D. is a Sleep Medicine (Psychiatry & Neurology) Physician provider in Portland, OR (NPI 1225141823).
Provider details
- NPI number
- 1225141823
- Entity type
- Individual
- Primary specialty
- Sleep Medicine (Psychiatry & Neurology) PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- OR MD18493 (OR)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Other Service Providers
Other Service Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 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
Mailing address
Registry dates
- Enumerated
- 2006-08-16
- Last updated
- 2014-03-10
Frequently asked questions
- What is Gregory Clark's NPI number?
- Gregory Clark's National Provider Identifier (NPI) is 1225141823, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Gregory Clark's specialty?
- Gregory Clark is listed in the NPPES registry with a primary specialty of Sleep Medicine (Psychiatry & Neurology) Physician (Allopathic & Osteopathic Physicians).
- Where is Gregory Clark located?
- Gregory Clark's practice location on file with NPPES is 11790 Sw Barnes Rd, Portland, OR 97225-5934.
- What is Gregory Clark's phone number?
- The practice phone number listed in the NPPES registry for Gregory Clark is (503) 228-4414.
- Does Gregory Clark accept Medicare?
- Gregory Clark is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Gregory Clark's NPI active?
- Yes — Gregory Clark's NPI (1225141823) is active in the NPPES registry as of the last update on 2014-03-10.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.