Marvin Ryou, M.D.
NPI 1821104787 · Gastroenterology Physician · Boston, MA
Enrolled with Medicare as Practitioner - Gastroenterology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Marvin Ryou, M.D. is a Gastroenterology Physician provider in Boston, MA (NPI 1821104787).
Provider details
- NPI number
- 1821104787
- Entity type
- Individual
- Primary specialty
- Gastroenterology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- 225849 (MA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
19 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
408 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Review By Radiologist of Image From Tube Placement Into Bile Duct Using an Endoscope74328 | 49 | $24 |
| Biopsy of Esophagus, Stomach, And/Or Upper Small Bowel Using a Flexible Endoscope43239 | 45 | $74 |
| Ultrasound Guided Needle Aspiration Or Biopsy of Esophagus, Stomach, And/Or Upper Small Bowel Using a Flexible Endoscope43242 | 42 | $248 |
| Ultrasound Exam of Esophagus, Stomach, And/Or Upper Small Bowel Using a Flexible Endoscope43259 | 41 | $205 |
| Removal of Stone Or Debris From Bile Or Pancreatic Duct Using a Flexible Endoscope43264 | 35 | $157 |
| Insertion of Stent Into Pancreatic Or Bile Duct Using a Flexible Endoscope43274 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$22,787 across 38 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-08-22
- Last updated
- 2012-07-19
Frequently asked questions
- What is Marvin Ryou's NPI number?
- Marvin Ryou's National Provider Identifier (NPI) is 1821104787, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Marvin Ryou's specialty?
- Marvin Ryou is listed in the NPPES registry with a primary specialty of Gastroenterology Physician (Allopathic & Osteopathic Physicians).
- Where is Marvin Ryou located?
- Marvin Ryou's practice location on file with NPPES is 75 Francis St, Boston, MA 02115-6110.
- What is Marvin Ryou's phone number?
- The practice phone number listed in the NPPES registry for Marvin Ryou is (617) 732-5500.
- Does Marvin Ryou accept Medicare?
- Marvin Ryou is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Marvin Ryou's NPI active?
- Yes — Marvin Ryou's NPI (1821104787) is active in the NPPES registry as of the last update on 2012-07-19.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.