Myfanwy Callahan, M.D.
NPI 1538428685 · Internal Medicine Physician · Medford, MA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Myfanwy Callahan, M.D. is a Internal Medicine Physician provider in Medford, MA (NPI 1538428685).
Provider details
- NPI number
- 1538428685
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Female
- Sole proprietor
- No
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Student, Health Care
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
14 yrs in NPPES registry
- Profile completeness25% of score
83% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
2,927 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) |
|---|---|---|
| Insertion of Needle Into Vein for Collection of Blood Sample36415 | 521 | $9 |
| Hemoglobin A1c Level83036 | 246 | $10 |
| Blood Test, Lipids (cholesterol and Triglycerides)80061 | 238 | $13 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 | 213 | $52 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 189 | $85 |
| Blood Creatinine Level82565 | 146 | $5 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 150 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 640 | 185 |
| Lisinopril | 319 | 91 |
| Levothyroxine Sodium | 312 | 88 |
| Gabapentin | 304 | 65 |
| Omeprazole | 286 | 93 |
| Amlodipine Besylate | 278 | 87 |
| Lorazepam |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$32 across 1 record (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
- 2012-05-10
- Last updated
- 2021-01-07
- Certified
- 2021-01-07
Frequently asked questions
- What is Myfanwy Callahan's NPI number?
- Myfanwy Callahan's National Provider Identifier (NPI) is 1538428685, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Myfanwy Callahan's specialty?
- Myfanwy Callahan is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Myfanwy Callahan located?
- Myfanwy Callahan's practice location on file with NPPES is 26 City Hall Mall, Medford, MA 02155-4754.
- What is Myfanwy Callahan's phone number?
- The practice phone number listed in the NPPES registry for Myfanwy Callahan is (781) 306-5130.
- Does Myfanwy Callahan accept Medicare?
- Myfanwy Callahan is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Myfanwy Callahan's NPI active?
- Yes — Myfanwy Callahan's NPI (1538428685) is active in the NPPES registry as of the last update on 2021-01-07.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.