Physician Profile
Ann Marie Stephenson Thomas, D.O.
Unclaimed ProfileAbout Dr. Stephenson Thomas
Ann Marie Stephenson Thomas, D.O. is a healthcare provider in Rockville, MD specializing in gastroenterology. Ann Marie trained at Philadelphia College of Osteopathic Medicine, graduating in 2003. Medicare claims data shows Ann Marie provided 455 services to 425 patients. The services billed most often include biopsy of large bowel using a flexible endoscope, established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more, and established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more. This provider record is associated with NPI 1376742601.
Factual summary compiled by Guide.md from public records; not written by this provider.
Education & Training
Specialty
Credentials & Licensing
Medicare information
Exactly as CMS reports it (National Downloadable File, Opt-Out Affidavits, Order & Referring). Not an insurance directory; confirm coverage with the office.
Contact Information
- (301) 251-9555
- Email not available
Practice Locations
9420 KEY WEST AVENUE SUITE 202
Rockville, MD 20850
Conditions Commonly Evaluated or Treated
Within Gastroenterology generally. Availability varies by clinician, training and location — this profile has not been claimed, so nothing here is a personal claim by the provider.
Conditions
Most searched conditions
- Acid reflux
- Celiac disease
- Crohn's disease
- Hemorrhoids
- IBS
- Swallowing difficulties
- Ulcerative colitis
Biliary and pancreas
Colon and anorectal
Esophagus and swallowing
Functional bowel and motility
Liver
- Ascites
- Autoimmune hepatitis
- Cirrhosis
- Fatty liver disease
- Hemochromatosis
- Hepatitis B
- Hepatitis C
- Portal hypertension
Stomach and duodenum
Bowel & Colon
Digestive Symptoms
Gallbladder & Bile Ducts
Procedures & services
Most searched procedures
Lower endoscopy
Upper endoscopy
Capsule and physiology testing
Diagnostic Testing
Liver procedures
Treatments
Procedures Most Often Billed to Medicare
455 services · 425 patients · 8 distinct codes
| Procedure | Type | Code | Services | Compared with peers |
|---|---|---|---|---|
| Biopsy of large bowel using a flexible endoscope | Procedure | 45380 |
94 | More often than most peers in Gastroenterology |
| Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope | Procedure | 43239 |
74 | As often as other peers in Gastroenterology |
| Removal of polyps or growths of large bowel using an endoscope with mechanical snare | Procedure | 45385 |
18 | Less often than most peers in Gastroenterology |
| Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more | Office visit | 99213 |
93 | More often than most peers in Gastroenterology |
| Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more | Office visit | 99214 |
74 | As often as other peers in Gastroenterology |
| New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more | Office visit | 99203 |
54 | More often than most peers in Gastroenterology |
| New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more | Office visit | 99204 |
30 | As often as other peers in Gastroenterology |
| Colorectal cancer screening; colonoscopy on individual at high risk | Billing code | G0105 |
18 | As often as other peers in Gastroenterology |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
Related providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Other gastroenterologists at this location 1
Same specialty, same street address — most likely the same department or group.
Related specialists at this location 1
Clinically related specialties at the same address — the people this provider most likely works alongside.
Also at this address 4
Providers at the same street address. Each files their own registry entry, so a shared practice often appears under several different names.
More connections — 32 related providers in 4 groups
Other gastroenterologists in Rockville 8
Same specialty, same city.
Trained at Philadelphia College of Osteopathic Medicine 8
Other providers in the same specialty who trained at the same institution.
Class of 2003 at Philadelphia College of Osteopathic Medicine 8
Providers who graduated from the same medical school in the same year.
Also performs Biopsy of large bowel using a flexible endoscope 8
Providers in MD who bill this service to Medicare most often.
Common questions
What does Ann Marie Stephenson Thomas specialize in?
Ann Marie Stephenson Thomas is a gastroenterologist in Rockville, MD. That is the designation recorded for this NPI in the federal registry, where it is listed as “Gastroenterology”.
NPI registry
Where is Ann Marie Stephenson Thomas located?
Ann Marie Stephenson Thomas is listed at 9420 Key West Avenue Suite 202, Rockville, MD 20850. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
What is Ann Marie Stephenson Thomas's phone number?
The number on file is (301) 251-9555. Contact the office directly to confirm availability and scheduling.
NPI registry
What is the NPI for Ann Marie Stephenson Thomas?
Ann Marie Stephenson Thomas's National Provider Identifier is 1376742601. It is issued by the Centers for Medicare & Medicaid Services and is unique and permanent — it does not change if they move practice.
NPI registry
Where did Ann Marie Stephenson Thomas train?
Ann Marie Stephenson Thomas attended Philadelphia College of Osteopathic Medicine, graduating in 2003. This comes from the CMS National Downloadable File.
CMS public data
How much experience does Ann Marie Stephenson Thomas have?
Ann Marie Stephenson Thomas has 23 years experience. Calculated from a graduation year of 2003, reported in the CMS National Downloadable File.
CMS public data
What does Ann Marie Stephenson Thomas do most often?
According to Medicare billing data, Ann Marie Stephenson Thomas performs procedures including biopsy of large bowel using a flexible endoscope, biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope and removal of polyps or growths of large bowel using an endoscope with mechanical snare, alongside routine visits and testing. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Is Ann Marie Stephenson Thomas's profile verified?
Not yet. This profile is built from public federal data and has not been confirmed by Ann Marie Stephenson Thomas. If this is you, claiming it is free.
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