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Dr. Mark Louis Simpson, PHD, CCC/SLP

Dr. Mark Louis Simpson is a Speech-Language Pathologist provider (Speech-Language Pathologist) practicing in Detroit, MI, registered in the NPPES registry with NPI 1316055379 since 2006. The credential PHD stands for Doctor of Philosophy.

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NPI 1316055379
Entity type Individual (Type 1)
Name Dr. Mark Louis Simpson
Credential PHD, CCC/SLP
Sex Male
Practice address 4100 JOHN R ST, KARMANOS CANCER CENTER-WERTZ CLINIC, Detroit, MI, 48201
Phone 8005276266
Fax 3135768381
Enumeration date 2006-08-29
Last updated in NPPES 2018-03-27

Taxonomy & licenses

Taxonomy code Specialty Primary License State
235Z00000X Speech-Language Pathologist Primary

PHD — Doctor of Philosophy: A doctoral degree; in healthcare often held by clinical psychologists and researchers. About the PHD credential

Copy-ready billing details
Provider: Mark Simpson, PHD, CCC/SLP
NPI: 1316055379
Taxonomy: 235Z00000X (Speech-Language Pathologist)
Address: 4100 JOHN R ST, KARMANOS CANCER CENTER-WERTZ CLINIC, Detroit, MI, 48201

Other providers at this practice address

NPI Name Type Specialty Location
1073430138 Kristen Moerchen Individual Acute Care Nurse Practitioner Detroit, MI
1518966316 Cynthia Marsack Individual Nurse Practitioner Detroit, MI
1366443137 Maria Vlachaki Individual Radiation Oncology Physician Detroit, MI
1669473146 Deborah Olszewski Individual Nurse Practitioner Detroit, MI
1275520512 Gina Fundaro Individual Diagnostic Radiology Physician Detroit, MI
1386632057 Wasif Saif Individual Hematology & Oncology Physician Detroit, MI
1457332579 Christine Rymal Individual Adult Health Nurse Practitioner Detroit, MI
1699756213 Laurie Freeman-Gibb Individual Adult Health Nurse Practitioner Detroit, MI

Verify this record

Cross-check NPI 1316055379 against the authoritative CMS record: view Dr. Mark Louis Simpson on the official NPPES registry .

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 or validate an NPI number.

Frequently asked questions

Is NPI 1316055379 active?
Yes — as of the latest NPPES snapshot, NPI 1316055379 is active (record last updated 2018-03-27).
How do I verify Mark Simpson's NPI record?
Cross-check NPI 1316055379 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2018-03-27.