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

Dr. Diane Sizer, PHD

Individual provider Psychologist · NPI 1265478259

Dr. Diane Sizer, PHD is a Clinical Psychologist in Southampton, Pennsylvania. Qualified in 1993, 33 years ago. Practices with Growth Opportunity Center, a 27-clinician group, works from 2 locations and accepts Medicare assignment. Licensed in Pennsylvania.

Years since qualifying
33
Licensed in
PA
In the registry since
2006
Specialties on file
2
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

928 Jaymor Rd Ste B-150
Southampton, PA 18966-3853
Phone: (215) 947-8654
Fax: (215) 938-7607
Show map & directions

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

Additional practice locations (1)

  • 928 Jaymor Rd Ste B-150, Southampton, PA 18966-3853 — (856) 745-9579

Specialties & licences

Psychologist (primary) Taxonomy 103T00000X · Licence PS008239L (PA)
Psychologist Taxonomy 103T00000X · Licence PS-008239-L (PA)

Record details

NPI number1265478259
Entity typeIndividual (Type 1)
GenderFemale
Credentials PHD
Sole proprietorNo
NPI enumeratedJune 20, 2006
Last updated in NPPESJuly 3, 2024
Certification dateJuly 3, 2024
Mailing address928 Jaymor Rd Ste B-150, Southampton, PA 18966-3853

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyCLINICAL PSYCHOLOGIST
Medical schoolOTHER
Graduated 1993 (33 years in practice)
Group practice Growth Opportunity Center — 27 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

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