2026 NPPES data Internal Medicine Physician NPI 1073604781 M.D.
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THOMAS HARBISON, M.D.

Internal Medicine Physician in PORTLAND, Oregon. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
Prescribing volume
1K
Medicare Part D claims · 370 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
94%
generic claims · 6% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

THOMAS HARBISON, M.D. filed 1,490 Medicare Part D claims in 2023 as a Internal Medicine Physician in PORTLAND, Oregon, prescribing 94% generic.

1K
Part D claims, 2023
94%
generic prescribing

Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) — no proprietary rating or editorial opinion is applied.

THOMAS HARBISON, M.D.'s Medicare Part D volume vs every U.S. prescriber

Total Medicare Part D claims, 2023 — across all CMS prescribers nationally

1,490 Top 20% higher than 80% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). Below this entry. 400–600: 90,619 prescribers (7%). Below this entry. 600–800: 56,224 prescribers (4%). Below this entry. 800–1,000: 40,919 prescribers (3%). Below this entry. 1,000–1,200: 31,827 prescribers (2%). Below this entry. 1,200–1,400: 26,224 prescribers (2%). Below this entry. 1,400–1,600: 21,710 prescribers (2%). This entry sits in this band. 1,600–1,800: 19,072 prescribers (1%). Above this entry. 1,800–2,000: 16,451 prescribers (1%). Above this entry. 2,000–2,200: 213,991 prescribers (16%). Above this entry. This provider 0 2K+ every Part D prescriber (claims/yr), bucketed by value

Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source CMS Medicare Part D Prescriber Public Use File · 2023

Board-eligible specialty (heuristic — not verified)

THOMAS HARBISON, M.D. practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).

What does the federal data show about THOMAS HARBISON, M.D.?

Quality data not reported

NPI registry status

Active

Issued 09/27/2006

NPI 1073604781

Primary specialty

Internal Medicine Physician

High-volume

172,858 US NPIs in this specialty

Medicare Part D claims

1,490 45% vs specialty avg

2023 prescription claims

Specialty avg: 2,716

Specialty distribution in Oregon

How Internal Medicine Physician compares to other specialties among Oregon providers

Oregon providers

Internal Medicine Physician share within Oregon

1. Internal Medicine Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Internal Medicine Physician share within Oregon

Specialty board-certification context

Estimated specialty board-certified rate — Internal Medicine Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Internal Medicine Physician ABMS/AOA estimate

Est. board-certified rate (Internal Medicine Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Internal Medicine Physician) — ABMS / AOA estimate

The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.

Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).

THOMAS HARBISON, M.D. appears in the CMS NPPES registry as a Internal Medicine Physician provider holding M.D. credentials at 3550 N INTERSTATE AVE, PORTLAND, OR, 97227, with a listed phone of (503) 285-9321. NPI 1073604781 was issued on 09/27/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what HARBISON most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 1,490 prescription claims written by this provider, covering 370 Medicare beneficiaries and totaling roughly $49K in drug spend, split 6% brand-name and 94% generic by claim count. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Internal Medicine Physician is a high-volume specialty nationwide, with 172,858 enrolled providers across 56 states and an average of 2,716 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.

Practice Address

3550 N INTERSTATE AVE
PORTLAND, OR 97227

Provider Details

NPI 1073604781
Specialty Internal Medicine Physician
Credentials M.D.
Gender Male
NPI Issued 09/27/2006

Brand vs generic prescribing mix · Generic-heavy

THOMAS HARBISON, M.D. — brand share 6.0%
Specialty average (est.)

6% brand-name claims vs 94% generic, on 1,490 2023 Medicare Part D claims.

The federal Medicare Part D Generic Dispensing Rate national benchmark sits near 90% generic / 10% brand for primary-care prescribers, per CMS Office of the Actuary 2024 estimates. Higher brand share is common in specialty prescribing where generic equivalents are not available.

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

1,490
Total Claims
$49K
Total Drug Cost
370
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
3,988
Total Day Supply
119,434
Brand vs Generic
6% brand / 94% generic
Brand Drug Cost
$23K
Generic Drug Cost
$25K

Patient Demographics

Average Patient Age
75.7 years
Avg HCC Risk Score
1.12
Gender Split
37% female / 63% male

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

What THOMAS HARBISON, M.D. prescribes most

Top Medicare Part D drugs by claim count, 2023

claims
Source CMS Medicare Part D Prescriber Public Use File As of 2023
Drug Claims
Atorvastatin Calcium
190
Simvastatin
91
Amlodipine Besylate
67
Lisinopril
61
Atenolol
60
Pravastatin Sodium
59
Levothyroxine Sodium
58
Metformin Hcl Er
Metformin Hcl
51
Tamsulosin Hcl
49
Losartan Potassium
47

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

Internal Medicine Physician Overview

How THOMAS HARBISON, M.D. fits within the Internal Medicine Physician landscape nationally.

172,858
Internal Medicine Physician Providers in US
56
States with Internal Medicine Physician
2,716
Avg Claims per Provider

THOMAS HARBISON, M.D.'s 1,490 claims are below the specialty average of 2,716.

Nearby Internal Medicine Physician Providers in Oregon

Other clinicians with the same primary specialty enrolled in Oregon, drawn from the same CMS NPPES roster as HARBISON.

Compare Internal Medicine Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is THOMAS HARBISON, M.D.'s specialty?
THOMAS HARBISON, M.D. specializes in Internal Medicine Physician and practices in PORTLAND, Oregon. Credentials: M.D..
How much does THOMAS HARBISON, M.D. prescribe under Medicare Part D?
In 2023, THOMAS HARBISON, M.D. wrote 1,490 Medicare Part D claims totaling $49K in drug costs for 370 beneficiaries.
Where is THOMAS HARBISON, M.D. located?
THOMAS HARBISON, M.D. is located at 3550 N INTERSTATE AVE, PORTLAND, OR, 97227. Phone: (503) 285-9321.
What is THOMAS HARBISON, M.D.'s NPI number?
THOMAS HARBISON, M.D.'s National Provider Identifier (NPI) is 1073604781, issued on 09/27/2006.
Does THOMAS HARBISON, M.D. prescribe more brand-name or generic drugs?
THOMAS HARBISON, M.D.'s prescribing is 6% brand-name and 94% generic drugs by claim count, with $23K in brand drug costs.
How many Internal Medicine Physician providers are there in the US?
There are 172,858 Internal Medicine Physician providers across 56 states in the US. The average Internal Medicine Physician provider writes 2,716 Medicare Part D claims per year.
What drugs does THOMAS HARBISON, M.D. prescribe most often?
Based on 2023 Medicare Part D data, THOMAS HARBISON, M.D.'s most frequently prescribed drugs include Atorvastatin Calcium, Simvastatin, Amlodipine Besylate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does THOMAS HARBISON, M.D. accept Medicare?
THOMAS HARBISON, M.D. appears in CMS Medicare data with 1,490 Part D claims and 370 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify THOMAS HARBISON, M.D.'s credentials?
THOMAS HARBISON, M.D.'s NPI is 1073604781 with credentials M.D.. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.

Data Sources

Provider Directory
CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
Specialty Classification
NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
Prescribing Data
CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
Limitations
Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.

See our complete data methodology for details on how we collect and process government data.

Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).

Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology