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

MS. Mary Hollis Johnston, PHD

Individual provider Psychologist · NPI 1790760023

MS. Mary Hollis Johnston, PHD is a Psychologist in Chicago, Illinois. Practices as a sole proprietor. Licensed in Illinois.

Licensed in
IL
In the registry since
2005
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

4820 S Greenwood Ave
Chicago, IL 60615-1914
Phone: (773) 624-8181
Fax: (773) 624-8181
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Psychologist (primary) Taxonomy 103T00000X (IL)

Record details

NPI number1790760023
Entity typeIndividual (Type 1)
GenderFemale
Credentials PHD
Sole proprietorYes
NPI enumeratedDecember 9, 2005
Last updated in NPPESJuly 8, 2007

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