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

Individual provider Clinical Neuropsychologist · NPI 1346457017

Mark Gregory Kiefner, PHD is a Clinical Neuropsychologist in Portland, Maine. Licensed in Maine. Registered with an NPI since 2007.

Licensed in
ME
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.

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Practice location Address checks out

26 Portland St
Portland, ME 04101 Not confirmed with CMS for 19 years — call before visiting
Phone: (207) 761-8402
Fax: (207) 761-8405
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Clinical Neuropsychologist (primary) Taxonomy 103G00000X · Licence PS815 (ME)

Record details

NPI number1346457017
Entity typeIndividual (Type 1)
GenderMale
Credentials PHD
Sole proprietorNo
NPI enumeratedMay 16, 2007
Last updated in NPPESJuly 8, 2007

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