John D. Sawyer, PHD
NPI 1649462276 · Clinical Psychologist · Fullerton, CA
John D. Sawyer, PHD is a Clinical Psychologist organization in Fullerton, CA (NPI 1649462276).
Provider details
- NPI number
- 1649462276
- Entity type
- Organization
- Primary specialty
- Clinical PsychologistBehavioral Health & Social Service Providers
- Organization subpart
- No
- Authorized official
- Alison Nathan, Clinical Psychologist(714) 871-9732
- License
- PSY 11021 (CA)
Specialties & taxonomies
Behavioral Health & Social Service Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
18 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
Other names (DBA / former)
- Doing business as
- Nathan & Sawyer
Registry dates
- Enumerated
- 2007-08-17
- Last updated
- 2007-08-17
Frequently asked questions
- What is John D. Sawyer, PHD's NPI number?
- John D. Sawyer, PHD's National Provider Identifier (NPI) is 1649462276, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What type of organization is John D. Sawyer, PHD?
- John D. Sawyer, PHD is classified in the NPPES registry as Clinical Psychologist (Behavioral Health & Social Service Providers).
- Where is John D. Sawyer, PHD located?
- John D. Sawyer, PHD's practice location on file with NPPES is 680 Langsdorf Dr, Fullerton, CA 92831-3702.
- What is John D. Sawyer, PHD's phone number?
- The practice phone number listed in the NPPES registry for John D. Sawyer, PHD is (714) 871-9732.
- Who is the authorized official for John D. Sawyer, PHD?
- The authorized official listed on John D. Sawyer, PHD's NPPES record is Alison Nathan, Clinical Psychologist. The authorized official registers and maintains the organization's NPI and is not necessarily its owner.
- Is John D. Sawyer, PHD's NPI active?
- Yes — John D. Sawyer, PHD's NPI (1649462276) is active in the NPPES registry as of the last update on 2007-08-17.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.