DR. VIVIAN HSUN-CHIEN CHOU MD
NPI 1457573420
Allergy & Immunology in Evanston, IL

Q: What is Vivian Chou's NPI number?

The NPI number for Vivian Chou is 1457573420. It was assigned to this individual provider in the NPPES registry on May 2, 2007.

Q: What is Vivian Chou's specialty?

The primary specialty registered for this NPI is Allergy & Immunology with taxonomy code 207K00000X.

Q: When was this NPI record last updated?

The NPPES record for Vivian Chou was last updated on December 6, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 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.

Active since May 02, 2007PECOS EnrolledAccepts Medicare Assignment

2500 RIDGE AVE, SUITE 211A, EVANSTON, IL 60201(847) 328-7909(847) 328-7919 Get Directions Write a Review

NPPES record last updated: December 6, 2021. Verified against the NPPES registry weekly; last sync: October 25, 2026.

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About Dr. Vivian Hsun-chien Chou Md NPPES

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

DR. VIVIAN HSUN-CHIEN CHOU MD (NPI 1457573420) is an individual allergy & immunology provider in Evanston, Illinois, licensed in Illinois (036114020) and active in the NPI registry since May 2007. She is enrolled in Medicare PECOS, is affiliated with Northwestern Medicine Central Dupage Hospital, and is a graduate of University Of Illinois College Of Med (chi/peor/rock/chm-urb) (2002).

NPPES Registry Identity

NPI1457573420

Entity TypeIndividualFemale

Primary Taxonomy207K00000X

Provider Legal NameDR. VIVIAN HSUN-CHIEN CHOUCredential: MD

Location Address2500 RIDGE AVE, SUITE 211AEvanston, IL 60201-2455

Mailing Address2500 Ridge Ave, Suite 211aEvanston, IL 60201 · (847) 328-7909 · Fax (847) 328-7919

Phone(847) 328-7909

Fax(847) 328-7919

Sole ProprietorYes

Medical School CMSUniversity Of Illinois College Of Med (chi/peor/rock/chm-urb)Graduated 2002

Enumeration DateMay 2, 2007

Last NPPES UpdateDecember 6, 2021

NPPES CertifiedDecember 6, 2021

✔ NPI 1457573420 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyAllergy & ImmunologyAllopathic & Osteopathic Physicians

Taxonomy Code207K00000X

License✔ Licensed in IL · 036114020

Definition

An allergist-immunologist is trained in evaluation, physical and laboratory diagnosis, and management of disorders involving the immune system. Selected examples of such conditions include asthma, anaphylaxis, rhinitis, eczema, and adverse reactions to drugs, foods, and insect stings as well as immune deficiency diseases (both acquired and congenital), defects in host defense, and problems related to autoimmune disease, organ transplantation, or malignancies of the immune system.

2500 RIDGE AVE, Evanston, IL 60201

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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter Health, Ambetter Health of Delaware, Oscar Health.Insurance ›

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. Vivian Hsun-chien Chou Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID1355435280

PECOS Enrollment IDI20070921000572

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 Vivian Chou reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Illinois Allergy And Asthma Specialists Sc

Same address

Allergy & Immunology

2500 RIDGE ROAD, SUITE 211A CO BUILDING
Evanston, IL 60201

Reassigned Medicare billing, Illinois enrollment
2 clinicians in this Medicare group

NPI 1386964252 (847) 328-7909

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 3

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.

New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204

This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.

23 services23 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.

20 services18 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.

19 services15 patients

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Northwestern Medicine Central Dupage Hospital

Acute Care Hospitals · Winfield, IL

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number140242

Location25 North Winfield RoadWinfield, IL 60190 · Du Page County

Emergency services Birthing friendly

Referred Medical Equipment & Supplies CMS DME claims 2

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Supplies for maintenance of non-insulin drug infusion catheter, per week (list drugs separately) A4221

DME-Other DME · category DE017N

1 supplier12 claims12 services$18.43 avg. paid by Medicare

Injection, immune globulin (hizentra), 100 mg J1559

Treatment-Injections and Infusions (nononcologic) · category RI008N

1 supplier12 claims7,680 services$9.54 avg. paid by Medicare

Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

Other Providers at the Same Location NPPES 20

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

NORTH SHORE ASSOCIATES IN GYNECOLOGY AND OBSTETRICS, S.C.

Specialist

2500 RIDGE AVE, SUITE 301
EVANSTON, IL 60201

Cook County (847) 475-1224

DR. KARI LEANN CHASE DPM

Podiatrist (Foot & Ankle Surgery)

2500 RIDGE AVE, SUITE #110
EVANSTON, IL 60201

Cook County (847) 475-9030

NORTH SHORE PHYSICIANS GROUP, LLC

Internal Medicine

2500 RIDGE AVE, STE 210
EVANSTON, IL 60201

Cook County (847) 491-0888

ELIZABETH KING WOO-STRAUSS M.D.

Internal Medicine

2500 RIDGE AVE, SUITE 104
EVANSTON, IL 60201

Cook County (847) 869-1192

DR. NOEL L. BLACKBURN LCSW, PH.D.

Social Worker (Clinical)

2500 RIDGE AVE, SUITE 305
EVANSTON, IL 60201

Cook County (847) 328-6999

POLLY SUE REESE DDS

Dentist (General Practice)

2500 RIDGE AVE, SUITE 102
EVANSTON, IL 60201

Cook County (847) 869-1272

BRUCE H DOBLIN, MD, SC

Internal Medicine

2500 RIDGE AVE, SUITE # 210
EVANSTON, IL 60201

Cook County (847) 328-6440

STEPHEN A. LIPSCHULTZ MD

Internal Medicine

2500 RIDGE AVE
EVANSTON, IL 60201

Cook County (847) 869-6200

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 Vivian Chou's NPI number?

The NPI number for Vivian Chou is 1457573420. It was assigned to this individual provider in the NPPES registry on May 2, 2007.

Where is Vivian Chou located?

Vivian Chou practices at 2500 Ridge Ave Suite 211A, Evanston, IL 60201. The listed phone number is (847) 328-7909.

What is Vivian Chou's specialty?

The primary specialty registered for this NPI is Allergy & Immunology with taxonomy code 207K00000X.

Is Vivian Chou enrolled in Medicare?

Yes. Vivian Chou is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organization bills Medicare for Vivian Chou's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Vivian Chou reassigns Medicare benefits to Illinois Allergy And Asthma Specialists Sc (Evanston, IL). 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 Vivian Chou's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Vivian Chou accept?

Health plans from Ambetter Health, Ambetter Health of Delaware and Oscar Health list Vivian Chou as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Vivian Chou affiliated with any hospitals?

According to CMS data, Vivian Chou is affiliated with Northwestern Medicine Central Dupage Hospital.

When was this NPI record last updated?

The NPPES record for Vivian Chou was last updated on December 6, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 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.