Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Katherine Lynn Klaassen, MD

Geriatric Psychiatry Physician in Muskogee, OK · enumerated 2006.

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

National Provider Identifier

1114937034

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Registry record

Entity type Individual (Type 1)

Name Katherine Lynn Klaassen

Credential MD

Sex Female

Practice address Muskogee, OK, 74401

Phone (918) 680-3699

Fax (918) 680-3701

Enumeration date Aug 9, 2006

Last updated in NPPES Sep 11, 2025

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

2084P0800X Psychiatry Physician Allopathic & Osteopathic Physicians · License 18532 (OK) Secondary

2084P0805X Geriatric Psychiatry Physician Allopathic & Osteopathic Physicians · License 18532 (OK) Primary

MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD 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.

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Frequently asked questions

How do I verify Katherine Klaassen's NPI record?

Cross-check NPI 1114937034 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

Is NPI 1114937034 active?

Yes, as of the latest NPPES snapshot, NPI 1114937034 is active (record last updated 2025-09-11).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2025-09-11.