2026 NPPES data Internal Medicine Physician NPI 1972881050 M.D.
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Thomas Xu, M.D.

Internal Medicine Physician in Wilton, Connecticut. 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 · 172 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
92%
generic claims · 8% brand-name · higher generic rates reduce patient out-of-pocket costs
MIPS score
79.1/100
▼ 4 pts below national avg 83.1 · [object Object]

What the federal data shows

Thomas Xu, M.D. reported a CMS MIPS final score of 79.1/100 — below the 83.1 national average — and filed 1,212 Medicare Part D claims in 2023.

79.1/100
MIPS score · -4 vs avg
1K
Part D claims, 2023
92%
generic prescribing
Likely
board-certified (heuristic)

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 Xu, M.D.'s MIPS score vs every scored U.S. clinician

CMS Merit-based Incentive Payment System (MIPS) final score, 2023 — the federal quality measure

79 30th percentile higher than 30% of 477,587 scored providers

0–10: 8,684 scored providers (2%). Below this entry. 10–20: 3,008 scored providers (1%). Below this entry. 20–30: 3,069 scored providers (1%). Below this entry. 30–40: 2,746 scored providers (1%). Below this entry. 40–50: 2,928 scored providers (1%). Below this entry. 50–60: 5,882 scored providers (1%). Below this entry. 60–70: 13,906 scored providers (3%). Below this entry. 70–80: 118,074 scored providers (25%). This entry sits in this band. 80–90: 129,887 scored providers (27%). Above this entry. 90–100: 189,403 scored providers (40%). Above this entry. This provider 0 100 every MIPS-scored clinician, bucketed by value

Each bar is a band; taller bars hold more scored providers. 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 Merit-based Incentive Payment System (MIPS) · 2023

Board certification likely (heuristic — not verified)

Thomas Xu, M.D. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + MIPS quality reporting + 1 hospital affiliation — signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).

What does the federal data show about Thomas Xu, M.D.?

Near national average

NPI registry status

Active

Issued 07/24/2011

NPI 1972881050

Primary specialty

Internal Medicine Physician

High-volume

172,858 US NPIs in this specialty

Medicare Part D claims

1,212 55% vs specialty avg

2023 prescription claims

Specialty avg: 2,716

MIPS final score

79.1/100 4 pts vs avg

Above neutral band

vs 83.1 national avg

Specialty distribution in Connecticut

How Internal Medicine Physician compares to other specialties among Connecticut providers

Connecticut providers

Internal Medicine Physician share within Connecticut

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

Medicare quality performance — MIPS

Thomas Xu, M.D.'s 2023 MIPS final score plotted against the Internal Medicine Physician national average

Near national average
MIPS Final Score
79.1/100
vs 83.1 national avg · 2023 performance year

MIPS final score (Internal Medicine Physician) — 79.1/100 vs national avg 83.1

0%100%National avg83%79.1%
MIPS final score (Internal Medicine Physician) — 79.1/100 vs national avg 83.1

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 Xu, M.D. appears in the CMS NPPES registry as a Internal Medicine Physician provider holding M.D. credentials at 372 DANBURY RD STE 197, Wilton, CT, 06897, with a listed phone of (203) 276-3366. NPI 1972881050 was issued on 07/24/2011. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what Xu 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 1,212 prescription claims written by this provider, covering 172 Medicare beneficiaries and totaling roughly $75K in drug spend, split 8% brand-name and 92% 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. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 79.1/100 for the 2023 performance year (Quality 73.2, Cost 57.9), compared with the national average of 83.1.

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

372 DANBURY RD STE 197
Wilton, CT 06897

Provider Details

NPI 1972881050
Specialty Internal Medicine Physician
Credentials M.D.
Gender Male
NPI Issued 07/24/2011

CMS Quality Score (MIPS)

Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.

79.0781
Final Score
Avg: 83.1
73.195
Quality
57.8987
Cost
99
Promoting Interoperability

Reporting: Group practice

Hospital and facility affiliations

Facilities where Thomas Xu, M.D. bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" — a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.

Stamford Health Medical Group Inc
Wilton, CT

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

Brand vs generic prescribing mix · Generic-heavy

Thomas Xu, M.D. — brand share 8.0%
Specialty average (est.)

8% brand-name claims vs 92% generic, on 1,212 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.

1,212
Total Claims
$75K
Total Drug Cost
172
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
2,898
Total Day Supply
85,654
Brand vs Generic
8% brand / 92% generic
Brand Drug Cost
$56K
Generic Drug Cost
$19K

Patient Demographics

Average Patient Age
74.6 years
Avg HCC Risk Score
0.75
Gender Split
44% female / 56% 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 Xu, 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
158
Lisinopril
87
Amlodipine Besylate
76
Levothyroxine Sodium
70
Losartan Potassium
60
Fluoxetine Hcl
55
Rosuvastatin Calcium
54
Tamsulosin Hcl
47
Metformin Hcl
39
Pravastatin Sodium
31

* 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 Xu, 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 Xu, M.D.'s 1,212 claims are below the specialty average of 2,716.

Nearby Internal Medicine Physician Providers in Connecticut

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

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

Before you book an appointment

Use this federal record as your verification checklist, not as a recommendation.

  • Confirm the NPI record is current in the official CMS registry — providers update their own NPPES details, and moves can lag. Verify this NPI
  • Check the active license and any disciplinary history with the Connecticut medical board — federal registration is not a license check. Credential verification guide
  • Weigh a second option: compare this provider with a nearby Internal Medicine Physician peer on Medicare volume and prescribing patterns. Compare providers

Medicare Part D and MIPS figures describe practice patterns in federal programs only — they are not quality ratings, and PlainDoctor does not rate, rank, or recommend providers.

Frequently Asked Questions

What is Thomas Xu, M.D.'s specialty?
Thomas Xu, M.D. specializes in Internal Medicine Physician and practices in Wilton, Connecticut. Credentials: M.D..
How much does Thomas Xu, M.D. prescribe under Medicare Part D?
In 2023, Thomas Xu, M.D. wrote 1,212 Medicare Part D claims totaling $75K in drug costs for 172 beneficiaries.
What is Thomas Xu, M.D.'s Medicare quality score?
Thomas Xu, M.D. has a CMS MIPS Final Score of 79.1/100 (Quality: 73.2, Cost: 57.9). The national average MIPS Final Score is 83.1. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is Thomas Xu, M.D. located?
Thomas Xu, M.D. is located at 372 DANBURY RD STE 197, Wilton, CT, 06897. Phone: (203) 276-3366.
What is Thomas Xu, M.D.'s NPI number?
Thomas Xu, M.D.'s National Provider Identifier (NPI) is 1972881050, issued on 07/24/2011.
Does Thomas Xu, M.D. prescribe more brand-name or generic drugs?
Thomas Xu, M.D.'s prescribing is 8% brand-name and 92% generic drugs by claim count, with $56K 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 Xu, M.D. prescribe most often?
Based on 2023 Medicare Part D data, Thomas Xu, M.D.'s most frequently prescribed drugs include Atorvastatin Calcium, Lisinopril, Amlodipine Besylate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Thomas Xu, M.D. accept Medicare?
Thomas Xu, M.D. appears in CMS Medicare data with 1,212 Part D claims and 172 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Thomas Xu, M.D.'s credentials?
Thomas Xu, M.D.'s NPI is 1972881050 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.
Quality Performance
CMS Merit-based Incentive Payment System (MIPS) — 2023 performance year.
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