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DR. ANN JOO LEE M.D.
NPI 1396979126
Internal Medicine - Gastroenterology in Downey, CA

Active since May 07, 2009PECOS EnrolledAccepts Medicare Assignment
81.54/100
CMS Quality Rating
10441 LAKEWOOD BLVD STE B, DOWNEY, CA 90241(562) 869-4497 Get Directions Write a Review

NPPES record last updated: December 29, 2025. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Dec 29, 2025, Dec 11, 2023 (2 updates tracked since 2023).

About Dr. Ann Joo Lee M.d. NPPES

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

DR. ANN JOO LEE M.D. (NPI 1396979126) is an individual gastroenterology provider in Downey, California, licensed in Illinois (036-167184) and active in the NPI registry since May 2009. She is enrolled in Medicare PECOS, is affiliated with Advocate Trinity Hospital, and maintains 2 additional practice locations.

NPPES Registry Identity

NPI1396979126
Entity TypeIndividualFemale
Primary Taxonomy207RG0100X
Provider Legal NameDR. ANN JOO LEECredential: M.D.
Location Address10441 LAKEWOOD BLVD STE BDowney, CA 90241-2871
Mailing AddressPo Box 35380Las Vegas, NV 89133-5380 · (702) 579-3203
Phone(562) 869-4497
Sole ProprietorNo
Medical School CMSOtherGraduated 2008
Enumeration DateMay 7, 2009
Last NPPES UpdateDecember 29, 20252 updates tracked since enumeration
NPPES CertifiedDecember 29, 2025
✔ NPI 1396979126 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · GastroenterologyAllopathic & Osteopathic Physicians
Taxonomy Code207RG0100X
Licenses✔ Licensed in IL · 036-167184✔ Licensed in CA · 136160
Definition
An internist who specializes in diagnosis and treatment of diseases of the digestive organs including the stomach, bowels, liver and gallbladder. This specialist treats conditions such as abdominal pain, ulcers, diarrhea, cancer and jaundice and performs complex diagnostic and therapeutic procedures using endoscopes to visualize internal organs.
10441 LAKEWOOD BLVD STE B, Downey, CA 90241
Open in Google Maps ↗

Secondary Practice Locations 2

Location 19831 S Western AveChicago, IL 60643-1740 · Phone (773) 445-3500
Location 28810 C Avenue, Apt 134Hesperia, CA 92345 · Phone (714) 788-8218

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. Ann Joo Lee M.d. 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 ID9739307638
PECOS Enrollment IDI20150817002129, I20231026000624
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.

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.

Initial hospital care with straightforward or low level of medical decision making, per day, if using time, at least 40 minutes 99221
Initial hospital inpatient care refers to the first day of your stay in the hospital. This service typically includes a 30-minute check-up with a healthcare professional. They'll assess your health, discuss your condition, and plan your treatment. It's part of ensuring you receive the best possible care.
28 services28 patients
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 43239
This procedure involves using a thin, flexible tube with a light and camera, known as an endoscope, to examine the esophagus, stomach, and upper part of the small intestine. Small tissue samples are taken for further examination to help diagnose various conditions.
20 services20 patients
Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 99222
Initial hospital inpatient care is a service where a healthcare provider spends about 50 minutes per day overseeing your care while you're admitted in the hospital. This includes reviewing your health status, planning your treatment, and ensuring your safety and comfort.
16 services16 patients
Biopsy of large bowel using a flexible endoscope 45380
A biopsy of the large bowel using a flexible endoscope is a procedure where a thin, flexible tube with a camera is inserted through the rectum to examine the bowel. If abnormal tissue is found, a small sample is taken for further examination. This helps in diagnosing conditions like inflammation, polyps, or cancer.
11 services11 patients

Hospital Affiliations CMS Care Compare

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

Advocate Trinity Hospital

Acute Care Hospitals · Chicago, IL
2/5 CMS rating
OwnershipVoluntary non-profit - Other
CMS Certification Number140048
Location2320 E 93rd StChicago, IL 60617 · Cook County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 90241 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
$142.39 typical visit price
range $62.96 – $187.60
Typical copayment $35.59 (range $15.74 – $46.90)
Most-billed visit code 99204
Established Patient
$109.96 typical visit price
range $20.84 – $153.61
Typical copayment $27.49 (range $5.21 – $38.40)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

81.54/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored as part of a group practice
Quality75.04
Promoting Interoperability100
Improvement Activities40
Cost63.42

Reported Quality Measures

Care Plan
Percentage of patients aged 65 years and older who have an advance care plan or surrogate decision maker documented in the medical record that an advance care plan was discussed but the patient did not wish or was not able to name a surrogate decision maker…
95%351 patients4/55-star benchmark: 100%
Documentation of Current Medications in the Medical Record
Percentage of visits for patients aged 18 years and older for which the eligible professional or eligible clinician attests to documenting a list of current medications using all immediate resources available on the date of the encounter.
100%1,331 patients5/55-star benchmark: 100%
e-Prescribing
At least one permissible prescription written by the MIPS eligible clinician is queried for a drug formulary and transmitted electronically using certified EHR technology.
30%373 patients1/55-star benchmark: 100%
Medication Reconciliation
The MIPS eligible clinician performs medication reconciliation for at least one transition of care in which the patient is transitioned into the care of the MIPS eligible clinician.
99%445 patients4/55-star benchmark: 100%
Patient-Specific Education
The MIPS eligible clinician must use clinically relevant information from CEHRT to identify patient-specific educational resources and provide access to those materials to at least one unique patient seen by the MIPS eligible clinician.
55%408 patients3/55-star benchmark: 100%
Preventive Care and Screening: Body Mass Index (BMI) Screening and Follow-Up Plan
Percentage of patients aged 18 years and older with a BMI documented during the current encounter or during the previous twelve months AND with a BMI outside of normal parameters, a follow-up plan is documented during the encounter or during the previous…
89%997 patients4/55-star benchmark: 100%
Preventive Care and Screening: Unhealthy Alcohol Use: Screening & Brief Counseling
Percentage of patients aged 18 years and older who were screened for unhealthy alcohol use using a systematic screening method at least once within the last 24 months AND who received brief counseling if identified as an unhealthy alcohol user
78%319 patients4/55-star benchmark: 100%
Provide Patient Access
At least one patient seen by the MIPS eligible clinician during the performance period is provided timely access to view online, download, and transmit to a third party their health information subject to the MIPS eligible clinician's discretion to withhold…
81%408 patients4/55-star benchmark: 100%
Secure Messaging
For at least one unique patient seen by the MIPS eligible clinician during the performance period, a secure message was sent using the electronic messaging function of CEHRT to the patient (or the patient-authorized representative), or in response to a secure…
60%408 patients4/55-star benchmark: 79%
Providers report different measures because they deliver different services; reporting more or less information is not a reflection of quality. Star ratings appear only where CMS assigned them.

Other Providers at the Same Location NPPES

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

DR. NIANI KALIFA CONERLY DNP, APRN, FNP-BC
Nurse Practitioner
10441 LAKEWOOD BLVD STE B
DOWNEY, CA 90241
Los Angeles County (562) 869-1089

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 Ann Lee's NPI number?

The NPI number for Ann Lee is 1396979126. It was assigned to this individual provider in the NPPES registry on May 7, 2009.

Where is Ann Lee located?

Ann Lee practices at 10441 Lakewood Blvd Ste B, Downey, CA 90241. The listed phone number is (562) 869-4497.

What is Ann Lee's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.

Is Ann Lee enrolled in Medicare?

Yes. Ann Lee 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.

Is Ann Lee affiliated with any hospitals?

According to CMS data, Ann Lee is affiliated with Advocate Trinity Hospital.

When was this NPI record last updated?

The NPPES record for Ann Lee was last updated on December 29, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 7 months 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.