William Sieff, MD
NPI 1780472407 · Student in an Organized Health Care Education/Training Program · New York, NY
William Sieff, MD is a Student in an Organized Health Care Education/Training Program provider in New York, NY (NPI 1780472407).
Provider details
- NPI number
- 1780472407
- Entity type
- Individual
- Primary specialty
- Student in an Organized Health Care Education/Training ProgramStudent, Health Care
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
Specialties & taxonomies
Student, Health Care
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
1 yr in NPPES registry
- Profile completeness38% of score
83% of core fields populated
- Practice footprint23% of score
2 documented practice locations
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
Additional practice locations (1)
- 506 Lenox AveNew York, NY 10037-1802Phone: (212) 939-1000
Registry dates
- Enumerated
- 2025-04-30
- Last updated
- 2025-04-30
- Certified
- 2025-04-30
Frequently asked questions
- What is William Sieff's NPI number?
- William Sieff's National Provider Identifier (NPI) is 1780472407, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Sieff's specialty?
- William Sieff is listed in the NPPES registry with a primary specialty of Student in an Organized Health Care Education/Training Program (Student, Health Care).
- Where is William Sieff located?
- William Sieff's practice location on file with NPPES is 1901 1st Ave, New York, NY 10029-7494.
- What is William Sieff's phone number?
- The practice phone number listed in the NPPES registry for William Sieff is (212) 423-6262.
- Is William Sieff's NPI active?
- Yes — William Sieff's NPI (1780472407) is active in the NPPES registry as of the last update on 2025-04-30.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.