Mark Aaron Gapen, PH.D.
Psychologist · Brookline, MA
Mark Aaron Gapen, PH.D. is a psychologist with a practice address in Brookline, Massachusetts, and NPI 1467786616, issued on Sep 21, 2009. Check the license with the Massachusetts board that licenses this profession; the federal record below is the public data PlainDoctor holds for this provider.
- Name
- Mark Aaron Gapen
- Credential
- PH.D.
- Primary taxonomy
- Psychologist 103T00000X
- Practice location
- 1269 Beacon St, Brookline, MA 02446
- Phone
- (617) 232-1303
- Enumerated
- Sep 21, 2009
- Record last updated
- Sep 21, 2009 (not updated in 17 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20160222002313); accepts Medicare assignment
- Medical or professional school
- Emory University School Of Medicine, 2009
- Entity
- Type 1 · individual
8 nearest psychologist records → All 2,367 in Massachusetts → Look up another NPI →
Also registered at 1269 Beacon St
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Michelle Harris, MA, LMHC, ATRMental Health Counselor1346465747
- Anna KharazMental Health Counselor1518203181
Verify Mark Aaron Gapen in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWhich Massachusetts board licenses this professionCheck the board
- 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Mark Aaron Gapen among 2,367 psychologist records in Massachusetts
Mark Aaron Gapen, PH.D. is one of 2,367 psychologist records with a practice address in Massachusetts. 11% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does not. Its NPI, issued in 2009, is newer than 50% of them.
- NPI issued2009 · 50% of these records are older, 48% newer
- In a Medicare fileNo · 11% of these records are
- In the CMS Doctors and Clinicians fileYes · 21% of these records are
- Graduated2009 · median 1997 among the 487 with a school on file
- Record last updated2009 · 68% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 103T00000X and a Massachusetts practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
98 psychologist records list a practice address in Brookline
They are 98 of the 2,357 NPPES records with a practice address in Brookline, and 2,367 psychologist records in Massachusetts. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.
All 2,367 in Massachusetts → Every provider in Brookline → Psychologist nationwide →
The 8 psychologist records with the nearest ZIP codes
- Lydia BaumrindBrookline, MA 024461861509937
- Richard Bristol, PSY.D.Brookline, MA 024461922091750
- Loren Brooks, PH.D.Brookline, MA 024461154379758
- Jonathan Brush, PHDBrookline, MA 024461730132846
- Jacqueline Buchin, PSYDBrookline, MA 024461508856246
- David Doolittle, PSYDBrookline, MA 024461982687380
- Marcel Fajnzylber, ED.D.Brookline, MA 024461821008947
- Jennifer Gistrak, PSY.D.Brookline, MA 024461205836673
Common questions
What is Mark Aaron Gapen, PH.D.'s NPI number?
Mark Aaron Gapen, PH.D.'s National Provider Identifier (NPI) is 1467786616, issued on Sep 21, 2009. An NPI identifies a provider in billing; it is not a license.
Where is Mark Aaron Gapen, PH.D. located?
The NPPES record lists a practice address at 1269 Beacon St, Brookline, MA, 02446. Phone: (617) 232-1303. Providers update this record themselves, so call before visiting.
How can I verify Mark Aaron Gapen, PH.D.'s license?
Search the Massachusetts board that licenses this profession; the NPPES record confirms identity only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.