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Dr. Diana L Maas, MD

Endocrinology, Diabetes & Metabolism Physician in Milwaukee, WI · enumerated 2006.

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

National Provider Identifier

1427009273

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Registry record

Entity type Individual (Type 1)
Name Dr. Diana L Maas
Credential MD
Sex Female
Practice address Froedtert & Med College Clin - East, 9200 West Wisconsin Avenue, Milwaukee, WI, 53226
Phone (414) 805-3666
Enumeration date May 15, 2006
Last updated in NPPES Jul 24, 2019

Taxonomy & licenses

207RE0101X Endocrinology, Diabetes & Metabolism Physician Allopathic & Osteopathic Physicians · License 27716 (WI) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
002000125G Other - HUMANA
1427009273 Medicaid WI -

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.

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Frequently asked questions

Where does Diana Maas practice?
The practice location on file with NPPES is in Milwaukee, WI. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Diana Maas?
The National Provider Identifier (NPI) for Diana Maas is 1427009273, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2019-07-24.