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DR. ANN MARIE STEPHENSON THOMAS D.O.
NPI 1376742601
Internal Medicine - Gastroenterology in Rockville, MD

Active since July 17, 2007PECOS EnrolledAccepts Medicare Assignment
9420 KEY WEST AVENUE, SUITE 202, ROCKVILLE, MD 20850(301) 251-9555(301) 309-0765 Get Directions Write a Review

NPPES record last updated: January 24, 2019. Verified against the NPPES registry weekly; last sync: August 16, 2026.

About Dr. Ann Marie Stephenson Thomas D.o. NPPES

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

DR. ANN MARIE STEPHENSON THOMAS D.O. (NPI 1376742601) is an individual gastroenterology provider in Rockville, Maryland, licensed in New Jersey (25MB08301600) and active in the NPI registry since July 2007. She is enrolled in Medicare PECOS, is affiliated with Adventist Healthcare Shady Grove Medical Center, and is a graduate of Philadelphia College Of Osteopathic Medicine (2003).

NPPES Registry Identity

NPI1376742601
Entity TypeIndividualFemale
Primary Taxonomy207RG0100X
Provider Legal NameDR. ANN MARIE STEPHENSON THOMASCredential: D.O.
Location Address9420 KEY WEST AVENUE, SUITE 202Rockville, MD 20850
Mailing Address9420 Key West Avenue, Suite 202Rockville, MD 20850 · (301) 251-9555 · Fax (301) 309-0765
Phone(301) 251-9555
Fax(301) 309-0765
Sole ProprietorNo
Medical School CMSPhiladelphia College Of Osteopathic MedicineGraduated 2003
Enumeration DateJuly 17, 2007
Last NPPES UpdateJanuary 24, 2019
✔ NPI 1376742601 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · GastroenterologyAllopathic & Osteopathic Physicians
Taxonomy Code207RG0100X
License✔ Licensed in NJ · 25MB08301600
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.
9420 KEY WEST AVENUE, Rockville, MD 20850
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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 Marie Stephenson Thomas D.o. 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 ID4587832308
PECOS Enrollment IDI20140402001871
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 8

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.

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.
94 services94 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.
93 services82 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.
74 services72 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.
74 services57 patients
New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more 99203
This service involves an initial office or outpatient visit for a new patient. The healthcare professional will spend 30-44 minutes understanding your health history, current issues, and discussing possible treatment plans. It's a comprehensive evaluation to start your healthcare journey.
54 services54 patients
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.
30 services30 patients

Hospital Affiliations CMS Care Compare

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

Adventist Healthcare Shady Grove Medical Center

Acute Care Hospitals · Rockville, MD
2/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number210057
Location9901 Medical Center DriveRockville, MD 20850 · Montgomery County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 20850 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
$147.85 typical visit price
range $65.18 – $194.86
Typical copayment $36.96 (range $16.29 – $48.71)
Most-billed visit code 99204
Established Patient
$113.72 typical visit price
range $21.40 – $158.88
Typical copayment $28.43 (range $5.35 – $39.72)
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.

Other Providers at the Same Location NPPES 4

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

PATRICIA A WIEDEMAN-STONE, PT P.T.
Physical Therapist
9420 KEY WEST AVENUE, SUITE 300
ROCKVILLE, MD 20850
Montgomery County (301) 294-0050
JENNIFER LYNN GILLOTT M.S.P.T.
Physical Therapist
9420 KEY WEST AVENUE, SUITE 300
ROCKVILLE, MD 20850
Montgomery County (301) 294-0050
KARIN COLETTE FICE OTR/L, CHT
Occupational Therapist
9420 KEY WEST AVENUE, SUITE 300
ROCKVILLE, MD 20850
Montgomery County (301) 294-0050
SHIRA SPILMAN PA-C
Physician Assistant
9420 KEY WEST AVENUE, SUITE 202
ROCKVILLE, MD 20850
Montgomery County (301) 251-9555

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 Marie Stephenson Thomas's NPI number?

The NPI number for Ann Marie Stephenson Thomas is 1376742601. It was assigned to this individual provider in the NPPES registry on July 17, 2007.

Where is Ann Marie Stephenson Thomas located?

Ann Marie Stephenson Thomas practices at 9420 Key West Avenue Suite 202, Rockville, MD 20850. The listed phone number is (301) 251-9555.

What is Ann Marie Stephenson Thomas's specialty?

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

Is Ann Marie Stephenson Thomas enrolled in Medicare?

Yes. Ann Marie Stephenson Thomas 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 Marie Stephenson Thomas affiliated with any hospitals?

According to CMS data, Ann Marie Stephenson Thomas is affiliated with Adventist Healthcare Shady Grove Medical Center.

When was this NPI record last updated?

The NPPES record for Ann Marie Stephenson Thomas was last updated on January 24, 2019. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 7 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.