Mark Williams, PH.D.
NPI 1699922112 · Clinical Neuropsychologist · Patton, CA
Mark Williams, PH.D. is a Clinical Neuropsychologist provider in Patton, CA (NPI 1699922112).
Provider details
- NPI number
- 1699922112
- Entity type
- Individual
- Primary specialty
- Clinical NeuropsychologistBehavioral Health & Social Service Providers
- Credential
- PH.D.
- Sex
- Male
- Sole proprietor
- No
Specialties & taxonomies
Behavioral Health & Social Service Providers
- Forensic Psychologist103TF0200X
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
17 yrs in NPPES registry
- Profile completeness38% of score
83% 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
- 2008-08-27
- Last updated
- 2013-07-29
Frequently asked questions
- What is Mark Williams's NPI number?
- Mark Williams's National Provider Identifier (NPI) is 1699922112, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Williams's specialty?
- Mark Williams is listed in the NPPES registry with a primary specialty of Clinical Neuropsychologist (Behavioral Health & Social Service Providers).
- Where is Mark Williams located?
- Mark Williams's practice location on file with NPPES is 3102 E. Highland Avenue, Patton, CA 92369.
- What is Mark Williams's phone number?
- The practice phone number listed in the NPPES registry for Mark Williams is (909) 425-7679.
- Is Mark Williams's NPI active?
- Yes — Mark Williams's NPI (1699922112) is active in the NPPES registry as of the last update on 2013-07-29.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.