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DR. CAROLINA EFREN DIAO M.D.
NPI 1275602344
Psychiatry & Neurology - Psychiatry in Lawrenceville, NJ

Active since November 06, 2006PECOS Enrolled
3131 PRINCETON PIKE STE 109, LAWRENCEVILLE, NJ 08648(609) 633-1500 Get Directions Write a Review

NPPES record last updated: January 26, 2017. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Dr. Carolina Efren Diao M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. CAROLINA EFREN DIAO M.D. (NPI 1275602344) is an individual psychiatry provider in Lawrenceville, New Jersey, licensed in New Jersey (MA71883) and active in the NPI registry since November 2006. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1275602344
Entity TypeIndividualFemale
Primary Taxonomy2084P0800X
Provider Legal NameDR. CAROLINA EFREN DIAOCredential: M.D.
Location Address3131 PRINCETON PIKE STE 109Lawrenceville, NJ 08648-2201
Mailing Address180 Ewingville RdEwing, NJ 08638-2425 · (609) 406-0181
Phone(609) 633-1500
Sole ProprietorNo
Enumeration DateNovember 6, 2006
Last NPPES UpdateJanuary 26, 2017
✔ NPI 1275602344 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPsychiatry & Neurology · PsychiatryAllopathic & Osteopathic Physicians
Taxonomy Code2084P0800X
License✔ Licensed in NJ · MA71883
Definition
A Psychiatrist specializes in the prevention, diagnosis, and treatment of mental disorders, emotional disorders, psychotic disorders, mood disorders, anxiety disorders, substance-related disorders, sexual and gender identity disorders and adjustment disorders. Biologic, psychological, and social components of illnesses are explored and understood in treatment of the whole person. Tools used may include diagnostic laboratory tests, prescribed medications, evaluation and treatment of psychological and interpersonal problems with individuals and families, and intervention for coping with stress, crises, and other problems.
3131 PRINCETON PIKE STE 109, Lawrenceville, NJ 08648
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Other Identifiers 3

Medicare UPINH53671NJ
Other053746C2DNJ · Medicare Provider Number
MedicaidD1053746NJ

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Carolina Efren Diao M.d. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Carolina Diao reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Arc Mercer, Inc.
5.2 mi
Clinic/Center
1542 KUSER RD STE B7
Hamilton, NJ 08619
  • Reassigned Medicare billing, New Jersey enrollment
  • 8 clinicians in this Medicare group
NPI 1518262203 (609) 989-9211

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 4

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Psychotherapy with evaluation and management visit, 30 minutes 90833
Psychotherapy with evaluation and management is a 30-minute session where a mental health professional talks with you about your concerns and feelings. They assess your mental health, provide support, and manage your treatment plan to help improve your well-being.
404 services117 patients
Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214
This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.
310 services89 patients
Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213
This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.
101 services41 patients
Psychiatric diagnostic evaluation with medical services 90792
A psychiatric diagnostic evaluation with medical services is a comprehensive assessment. It includes a detailed examination of your mental health and physical wellbeing, as well as your personal and family history. This evaluation aids in creating an effective treatment plan.
15 services15 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 08648 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$185.05 typical visit price
range $61.59 – $185.05
Typical copayment $46.26 (range $15.39 – $46.26)
Most-billed visit code 99205
Established Patient
$76.45 typical visit price
range $20.08 – $150.98
Typical copayment $19.11 (range $5.02 – $37.74)
Most-billed visit code 99213
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

MONICA ANN QUASTE MA
Counselor (Professional)
3131 PRINCETON PIKE STE 109
LAWRENCEVILLE, NJ 08648
Mercer County (609) 406-0181

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Carolina Diao's NPI number?

The NPI number for Carolina Diao is 1275602344. It was assigned to this individual provider in the NPPES registry on November 6, 2006.

Where is Carolina Diao located?

Carolina Diao practices at 3131 Princeton Pike Ste 109, Lawrenceville, NJ 08648. The listed phone number is (609) 633-1500.

What is Carolina Diao's specialty?

The primary specialty registered for this NPI is Psychiatry & Neurology, specializing in Psychiatry, with taxonomy code 2084P0800X.

Is Carolina Diao enrolled in Medicare?

Yes. Carolina Diao is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Carolina Diao's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Carolina Diao reassigns Medicare benefits to Arc Mercer, Inc. (Hamilton, NJ). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Carolina Diao's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Carolina Diao was last updated on January 26, 2017. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 9 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.