William Duffy, MD
NPI 1538108055 · Internal Medicine Physician · Conshohocken, PA
William Duffy, MD is a Internal Medicine Physician provider in Conshohocken, PA (NPI 1538108055).
Provider details
- NPI number
- 1538108055
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- MD060436L (PA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
20 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
1,028 Medicare services, 2024 (ranked within specialty)
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 methodology.
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) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 345 | $131 |
| Established Patient Office Or Other Outpatient Visit With High Level of Medical Decision Making, If Using Time, 40 Minutes Or More99215 | 163 | $183 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 | 127 | $134 |
| Visit Complexity Inherent to Evaluation and Management Associated With Medical Care Services That Serve As the Continuing Focal Point for All Needed Health Care Services And/Or With Medical Care Services That Are Part of Ongoing Care Related to a Patient'SG2211 | 104 | $17 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 78 | $92 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 74 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Amlodipine Besylate | 242 | 63 |
| Rosuvastatin Calcium | 196 | 62 |
| Atorvastatin Calcium | 152 | 46 |
| Levothyroxine Sodium | 102 | 29 |
| Lisinopril | 102 | 25 |
| Metformin Hclbrand: Metformin Hcl Er | 96 | 23 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-06-06
- Last updated
- 2026-03-18
- Certified
- 2026-03-18
Frequently asked questions
- What is William Duffy's NPI number?
- William Duffy's National Provider Identifier (NPI) is 1538108055, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Duffy's specialty?
- William Duffy is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is William Duffy located?
- William Duffy's practice location on file with NPPES is 161 Washington St, Conshohocken, PA 19428.
- What is William Duffy's phone number?
- The practice phone number listed in the NPPES registry for William Duffy is (610) 200-0250.
- Is William Duffy's NPI active?
- Yes — William Duffy's NPI (1538108055) is active in the NPPES registry as of the last update on 2026-03-18.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.