Thomas O'Connor, M.D.
NPI 1669507141 · Internal Medicine Physician · Weymouth, MA
Enrolled with Medicare as Practitioner - Hematology/Oncology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Thomas O'Connor, M.D. is a Internal Medicine Physician provider in Weymouth, MA (NPI 1669507141).
Provider details
- NPI number
- 1669507141
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- MD035011 (DC)
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 tenure28% of score
19 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
1,777 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 Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 1,219 | $70 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 376 | $103 |
| New Patient Office Or Other Outpatient Visit With a High Level of Medical Decision Making, If Using Time, 60 Minutes Or More99205 | 66 | $191 |
| New Patient Office Or Other Outpatient Visit With Moderate Level of Medical Decision Making, If Using Time, 45 Minutes Or More99204 | 58 | $140 |
| Established Patient Office Or Other Outpatient Visit With High Level of Medical Decision Making, If Using Time, 40 Minutes Or More99215 | 42 | $152 |
| Initial Hospital Care With Straightforward Or Low Level of Medical Decision Making, Per Day, If Using Time, at Least 40 Minutes |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 46 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Prednisone | 239 | 62 |
| Abiraterone Acetate | 194 | 38 |
| Letrozole | 131 | 41 |
| Ondansetron Hcl | 116 | 57 |
| Oxycodone Hcl | 97 | 24 |
| Bicalutamide | 94 | 45 |
| Prochlorperazine Maleate | 79 | 55 |
| Dexamethasone | 66 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-02-23
- Last updated
- 2014-01-21
Frequently asked questions
- What is Thomas O'Connor's NPI number?
- Thomas O'Connor's National Provider Identifier (NPI) is 1669507141, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Thomas O'Connor's specialty?
- Thomas O'Connor is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Thomas O'Connor located?
- Thomas O'Connor's practice location on file with NPPES is 51 Performance Dr, Weymouth, MA 02189-3141.
- What is Thomas O'Connor's phone number?
- The practice phone number listed in the NPPES registry for Thomas O'Connor is (781) 337-9091.
- Does Thomas O'Connor accept Medicare?
- Thomas O'Connor is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Thomas O'Connor's NPI active?
- Yes — Thomas O'Connor's NPI (1669507141) is active in the NPPES registry as of the last update on 2014-01-21.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.