Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.

Dr. Mark Theodore Simpson, PHD

Individual provider Clinical Psychologist · NPI 1285757013

Dr. Mark Theodore Simpson, PHD is a Clinical Psychologist in Johnson City, Tennessee. Works from 2 locations. Licensed in Tennessee.

Licensed in
TN
In the registry since
2007
What do these letters mean?
PHD — Doctor of Philosophy
A research doctorate. In healthcare it usually sits alongside a clinical licence.

See every abbreviation used in this directory →

Practice location Address checks out

119 Boone Ridge Dr Ste 201
Johnson City, TN 37615
Phone: (865) 673-6741
Fax: (865) 673-6634
Show map & directions

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 119 Boone Ridge Dr, Johnson City, TN 37615-4998 — (865) 673-6741

Specialties & licences

Clinical Psychologist (primary) Taxonomy 103TC0700X · Licence 3205 (TN)

Record details

NPI number1285757013
Entity typeIndividual (Type 1)
GenderMale
Credentials PHD
Sole proprietorNo
NPI enumeratedApril 8, 2007
Last updated in NPPESJune 25, 2018

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