Ken Zafren, MD
NPI 1366466120 · Emergency Medicine Physician · Stanford, CA
Enrolled with Medicare as Practitioner - Emergency Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Ken Zafren, MD is a Emergency Medicine Physician provider in Stanford, CA (NPI 1366466120).
Provider details
- NPI number
- 1366466120
- Entity type
- Individual
- Primary specialty
- Emergency Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- G70948 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
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
2 documented practice locations
- Medicare service volume (vs. specialty peers)28% of score
132 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) |
|---|---|---|
| Emergency Department Visit With High Level of Medical Decision Making99285 | 79 | $187 |
| Critical Care, First 30-74 Minutes99291 | 39 | $233 |
| Ultrasound of Heart, Follow-Up93308 | 14 | $28 |
Typical Medicare-allowed amounts for these services range $28–$233 (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
Additional practice locations (1)
- 4315 Diplomacy DrAnchorage, AK 99508-5926Phone: (907) 729-1729Fax: (907) 729-1759
Registry dates
- Enumerated
- 2006-07-26
- Last updated
- 2024-03-21
- Certified
- 2024-03-21
Frequently asked questions
- What is Ken Zafren's NPI number?
- Ken Zafren's National Provider Identifier (NPI) is 1366466120, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Ken Zafren's specialty?
- Ken Zafren is listed in the NPPES registry with a primary specialty of Emergency Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Ken Zafren located?
- Ken Zafren's practice location on file with NPPES is 300 Pasteur Dr, Stanford, CA 94305-2200.
- What is Ken Zafren's phone number?
- The practice phone number listed in the NPPES registry for Ken Zafren is (650) 723-0000.
- Does Ken Zafren accept Medicare?
- Ken Zafren is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Ken Zafren's NPI active?
- Yes — Ken Zafren's NPI (1366466120) is active in the NPPES registry as of the last update on 2024-03-21.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.