Individual provider

Abigail Sivan, PH.D.

Health Service Psychologist Psychologist Clinical Psychologist

Abigail Sivan, PH.D. is a Health Service Psychologist in Wilmette, IL, registered under NPI 1023093515. This provider registers 3 separate taxonomy codes, which usually means they practise across more than one recognised specialty. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.

Getting there

The practice address on file is 3330 OLD GLENVIEW RD SUITE 5, Wilmette, IL 60091. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

3330 OLD GLENVIEW RD SUITE 5, Wilmette, IL 60091 Open in Google Maps →

Credentials and Medicare

State licence
LicenceStateSpecialty
00092 IA Health Service Psychologist primary
00431 IA Psychologist

This provider holds licence 00092 issued in IA. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.

Medicare (PECOS)

This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.

What Health Service covers

A psychologist, certified/licensed at the independent practice level in his/her state, who is duly trained and experienced in the delivery of direct, preventative, assessment, and therapeutic intervention services to individuals whose growth, adjustment, or functioning is actually impaired or is demonstrably at high risk of impairment (1974). NUCC Health Care Provider Taxonomy, code 103TH0100X
Behavioral Health & Social Service Providers Psychologist Health Service

All registered taxonomy codes

This provider registers 3 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.

CodeSpecialtyLicenceState
103TH0100X Health Service Psychologist Health Service 00092 IA primary
103T00000X Psychologist 00431 IA
103TC0700X Clinical Psychologist Clinical IL

The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.

Full NPPES record

An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.

NPI1023093515 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateDec 7, 2005
Last updatedSep 11, 2025
StatusActive
Sole proprietorYes
CredentialPH.D.
Practice address 3330 OLD GLENVIEW RD
SUITE 5
Wilmette, IL 60091
(847) 251-3261
Fax (847) 730-3003
Mailing address 2000 DEWES ST
Glenview, IL 60025
This record was updated on Sep 11, 2025, which is recent enough that the contact details are likely still accurate.

Number check

1023093515 passes the NPI check digit test The final digit 5 matches the value computed from the first nine digits, so this is a well-formed NPI.
How the check works, step by step

Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.

Digit 8 0 8 4 0 1 0 2 3 0 9 3 5 1
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 0 4 3 0 9 6 5 2

Sum = 55 · next multiple of 10 = 60 · check digit = 5 · actual last digit = 5

A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.

Common questions

What is NPI number 1023093515?
NPI 1023093515 is the National Provider Identifier assigned to Abigail Sivan, PH.D. in Wilmette, IL. It is a 10-digit number issued by the Centers for Medicare & Medicaid Services and used on claims, referrals, and prescriptions to identify the provider.
What does Health Service cover?
A psychologist, certified/licensed at the independent practice level in his/her state, who is duly trained and experienced in the delivery of direct, preventative, assessment, and therapeutic intervention services to individuals whose growth, adjustment, or functioning is actually impaired or is demonstrably at high…
How do I contact Abigail Sivan, PH.D.?
The phone number on file with NPPES is (847) 251-3261, last updated Sep 11, 2025. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Is NPI 1023093515 a valid number?
Yes. 1023093515 passes the Luhn check digit validation that CMS uses for NPI numbers, and it resolves to an active record in the registry.
How to use this page. Everything here comes from public federal records. Tips Health does not verify quality of care, confirm that a licence is currently active, or check malpractice history, and accepts no fees for placement. A listing is not a recommendation. Verify independently before seeking care.