Mark Summerson, PHD, LLC
NPI 1447604509 · Psychologist · Pullman, WA
Enrolled with Medicare as Part B Supplier - Clinic/Group Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Summerson, PHD, LLC is a Psychologist organization in Pullman, WA (NPI 1447604509).
Provider details
- NPI number
- 1447604509
- Entity type
- Organization
- Primary specialty
- PsychologistBehavioral Health & Social Service Providers
- Organization subpart
- No
- Authorized official
- Mark Summerson, Psychologist(509) 330-5456
- License
- PY00002258 (WA)
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
10 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
- 2016-04-14
- Last updated
- 2016-04-14
Frequently asked questions
- What is Mark Summerson, PHD, LLC's NPI number?
- Mark Summerson, PHD, LLC's National Provider Identifier (NPI) is 1447604509, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What type of organization is Mark Summerson, PHD, LLC?
- Mark Summerson, PHD, LLC is classified in the NPPES registry as Psychologist (Behavioral Health & Social Service Providers).
- Where is Mark Summerson, PHD, LLC located?
- Mark Summerson, PHD, LLC's practice location on file with NPPES is 254 E Main St, Pullman, WA 99163-2678.
- What is Mark Summerson, PHD, LLC's phone number?
- The practice phone number listed in the NPPES registry for Mark Summerson, PHD, LLC is (509) 330-5456.
- Does Mark Summerson, PHD, LLC accept Medicare?
- Mark Summerson, PHD, LLC is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Who is the authorized official for Mark Summerson, PHD, LLC?
- The authorized official listed on Mark Summerson, PHD, LLC's NPPES record is Mark Summerson, Psychologist. The authorized official registers and maintains the organization's NPI and is not necessarily its owner.
- Is Mark Summerson, PHD, LLC's NPI active?
- Yes — Mark Summerson, PHD, LLC's NPI (1447604509) is active in the NPPES registry as of the last update on 2016-04-14.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.