NPI Portal NPI Lookup & Verification

Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. Madeline Duncan, DC

Chiropractor in Danville, CA · enumerated 2024 · practices at Madeline Duncan Chiropractic Corporation.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1841016938

Verified

See something wrong? Report a correction

Registry record

Entity type Individual (Type 1)
Name Dr. Madeline Duncan
Credential DC
Sex Female
Practice address 318 Diablo Rd Ste 245, Danville, CA, 94526
Phone (925) 290-1830
Enumeration date Nov 23, 2024
Last updated in NPPES Nov 23, 2024

Taxonomy & licenses

111N00000X Chiropractor Chiropractic Providers · License DC37081 (CA) Primary
DC · Doctor of Chiropractic: A licensed chiropractor focusing on musculoskeletal and nervous system disorders. About the DC credential

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

Read the full guide → Validate an NPI →

Frequently asked questions

What specialty is Madeline Duncan?
Madeline Duncan is registered in NPPES with the primary taxonomy of Chiropractor. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

Other providers at this practice address

Browse all →

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2024-11-23.