NPPES file of Aug 9, 2026

Dia O'Brien, APRN

Psychiatric/Mental Health Nurse Practitioner · New Haven, CT

Dia O'Brien, APRN is a psychiatric/mental health nurse practitioner with a practice address in New Haven, Connecticut, and NPI 1750168951, issued on Sep 11, 2023. Check the license (Connecticut 12121, as entered in NPPES) with the Connecticut board that licenses this profession; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1750168951
Name
Dia O'Brien
Credential
APRN
Primary taxonomy
Psychiatric/Mental Health Nurse Practitioner 363LP0808X
License number
12121 CT
Self-reported in NPPES; status is on the state search
Practice location
34 Park St, New Haven, CT 06519
Phone
(203) 974-7560
Enumerated
Sep 11, 2023
Record last updated
Sep 11, 2023
Medicare enrollment
Enrolled (PECOS I20240229001174); accepts Medicare assignment
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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8 nearest psychiatric/mental health nurse practitioner records → All 1,108 in Connecticut → Look up another NPI →

Also registered at 34 Park St

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Raina AggarwalStudent in an Organized Health Care Education/Training Program1154852374
  2. Mayra Aguirre, LCSWClinical Social Worker1326424938
  3. Edna Aklin, LCSWClinical Social Worker1407905805
  4. Milania Al-Jammaly, M.D.Psychiatry Physician1851704969
  5. Areej Ali, MDInternal Medicine Physician1629654629
  6. Margaret Allende, DNSC APRNClinical Nurse Specialist1386709756

Verify Dia O'Brien in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersWhich Connecticut board licenses this profession
    Search for license 12121    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Find the Connecticut license search

PlainDoctor does not match the HHS-OIG exclusion list to individual records: most entries carry no NPI. Search the OIG exclusion list by name.

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Bills Medicare through one group practice

  1. State OF ConnecticutFarmington, CT

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

Dia O'Brien among 1,108 psychiatric/mental health nurse practitioner records in Connecticut

Dia O'Brien, APRN is one of 1,108 psychiatric/mental health nurse practitioner records with a practice address in Connecticut. 70% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2023, is newer than 74% of them.

  • NPI issued2023 · 74% of these records are older, 19% newer
  • In a Medicare fileYes · 70% of these records are
  • In the CMS Doctors and Clinicians fileYes · 51% of these records are
  • Graduated2023 · median 2020 among the 566 with a school on file
  • Record last updated2023 · 38% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 363LP0808X and a Connecticut practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

88 psychiatric/mental health nurse practitioner records list a practice address in New Haven

They are 88 of the 9,793 NPPES records with a practice address in New Haven, and 1,108 psychiatric/mental health nurse practitioner records in Connecticut.

All 1,108 in Connecticut → Every provider in New Haven → Psychiatric/Mental Health Nurse Practitioner nationwide →

The 8 psychiatric/mental health nurse practitioner records with the nearest ZIP codes

  1. Gale Banks, APRNNew Haven, CT 065191891850020
  2. Eileen Bonyai, PMH NPNew Haven, CT 065191114083664
  3. Maurice Bunnell, APRNNew Haven, CT 065191194053777
  4. Kathryn Camizzi, APRNNew Haven, CT 065191760466957
  5. Tammy Cohen, RN,DNP, NP, PMHNPNew Haven, CT 065191205060795
  6. Max Greger-Moser, APRNNew Haven, CT 065191295136455
  7. Janice Jones, APRN BCNew Haven, CT 065191609931831
  8. Nicole MalettaNew Haven, CT 065191104265149

Common questions

What is Dia O'Brien, APRN's NPI number?

Dia O'Brien, APRN's National Provider Identifier (NPI) is 1750168951, issued on Sep 11, 2023. An NPI identifies a provider in billing; it is not a license.

Where is Dia O'Brien, APRN located?

The NPPES record lists a practice address at 34 Park St, New Haven, CT, 06519. Phone: (203) 974-7560. Providers update this record themselves, so call before visiting.

How can I verify Dia O'Brien, APRN's license?

NPPES lists Connecticut license number 12121, as entered by the provider. Search the Connecticut 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. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.

Written with AI tools from the named public files; every figure is computed from those files (how it is made).

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.