Willaim Decker, PH. D.
NPI 1033234950 · Cognitive & Behavioral Psychologist · Alexandria, VA
Enrolled with Medicare as Practitioner - Clinical Psychologist · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Willaim Decker, PH. D. is a Cognitive & Behavioral Psychologist provider in Alexandria, VA (NPI 1033234950).
Provider details
- NPI number
- 1033234950
- Entity type
- Individual
- Primary specialty
- Cognitive & Behavioral PsychologistBehavioral Health & Social Service Providers
- Credential
- PH. D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- 0810002331 (VA)
Specialties & taxonomies
Behavioral Health & Social Service Providers
Behavioral Health & Social Service Providers
Behavioral Health & Social Service Providers
Behavioral Health & Social Service Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
19 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
797 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. 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.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Psychotherapy, 1 Hour90837 | 646 | $162 |
| Psychotherapy, 30 Minutes90832 | 82 | $84 |
| Psychotherapy, 45 Minutes90834 | 69 | $110 |
Typical Medicare-allowed amounts for these services range $84–$162 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-03-20
- Last updated
- 2025-09-11
Frequently asked questions
- What is Willaim Decker's NPI number?
- Willaim Decker's National Provider Identifier (NPI) is 1033234950, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Willaim Decker's specialty?
- Willaim Decker is listed in the NPPES registry with a primary specialty of Cognitive & Behavioral Psychologist (Behavioral Health & Social Service Providers).
- Where is Willaim Decker located?
- Willaim Decker's practice location on file with NPPES is 1423 Powhatan St, Alexandria, VA 22314-1389.
- What is Willaim Decker's phone number?
- The practice phone number listed in the NPPES registry for Willaim Decker is (703) 836-3678.
- Does Willaim Decker accept Medicare?
- Willaim Decker is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Willaim Decker's NPI active?
- Yes — Willaim Decker's NPI (1033234950) is active in the NPPES registry as of the last update on 2025-09-11.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.