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Dr. Irwin Grossman Jr., PH.D.

Clinical Psychologist in Glendale, AZ · enumerated 2006.

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

National Provider Identifier

1205892056

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Registry record

Entity type Individual (Type 1)
Name Dr. Irwin Grossman Jr.
Credential PH.D.
Sex Male
Practice address 5757 W Thunderbird Rd, W-401, Glendale, AZ, 85306
Phone (602) 439-0475
Fax (602) 439-0106
Enumeration date Apr 21, 2006
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

103TC0700X Clinical Psychologist Behavioral Health & Social Service Providers · License 1302 (AZ) Primary
PHD · Doctor of Philosophy: A doctoral degree; in healthcare often held by clinical psychologists and researchers. About the PHD credential

Other identifiers

Identifier Type State Issuer
AZ0621030 Other AZ BC/BS ID

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

What specialty is Irwin Grossman?
Irwin Grossman is registered in NPPES with the primary taxonomy of Clinical Psychologist. 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.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.