NPI registry status
Active
2026 NPPES data Internal Medicine Physician NPI 1265401350 DO
Verify on CMS → William Lewis, DO
Internal Medicine Physician in Austin, Texas.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 172,858 in Internal Medicine Physician, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration, see our methodology.
Federal data, no proprietary rating.
We show these CMS records as-is - no composite score, no star rating, no editorial opinion layered on top.
Prescribing volume
8K
Medicare Part D claims · 942 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
89%
generic claims · 10% brand-name · higher generic rates reduce patient out-of-pocket costs
MIPS score
75/100
▼ 8 pts below national avg 83.1 · Above neutral
Industry payments
$787.37
45 payments · CMS Open Payments (Sunshine Act)
Source: CMS Medicare Part D Prescriber Public Use File, 2023
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
William Lewis, DO reported a CMS MIPS final score of 75/100 - below the 83.1 national average - and filed 8,487 Medicare Part D claims in 2023.
- 75/100
- MIPS score · -8 vs avg
- 8K
- Part D claims, 2023
- 89%
- 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.
William Lewis, DO's MIPS score vs every scored U.S. clinician
CMS Merit-based Incentive Payment System (MIPS) final score, 2023, the federal quality measure
75 15th percentile higher than 15% of 477,587 scored providers
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
Where William Lewis, DO sits
This provider among internal medicine physician peers
Across the 36,260 internal medicine physician providers who report both Medicare Part D prescribing and a MIPS quality score, William Lewis, DO writes more Part D claims than 90% of them and scores higher on MIPS quality than 14% - placing this provider in the high-volume, lower-quality quadrant. Volume reflects patient-panel size and specialty, not quality; the two axes are independent.
Part D claim volume vs MIPS quality, by specialty percentile
Each dot is one internal medicine physician peer from a representative sample of 60; the gold marker is William Lewis, DO. Source: CMS Medicare Part D Prescriber data and the CMS Merit-based Incentive Payment System, 2023.
✓
Board certification likely (heuristic, not verified)
William Lewis, DO 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 William Lewis, DO?
Below national averagePrimary specialty
Internal Medicine Physician
Medicare Part D claims
8,487 212% vs specialty avg
MIPS final score
75/100 8.1 pts vs avg
Specialty distribution in Texas
How Internal Medicine Physician compares to other specialties among Texas providers
Medicare quality performance, MIPS
William Lewis, DO's 2023 MIPS final score plotted against the Internal Medicine Physician national average
- MIPS Final Score
- 75/100
- vs 83.1 national avg · 2023 performance year
MIPS final score (Internal Medicine Physician) - 75/100 vs national avg 83.1
How MIPS and board certification work
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).
William Lewis, DO appears in the CMS NPPES registry as a Internal Medicine Physician provider holding DO credentials at 12221 N MOPAC EXPY, Austin, TX, 78758, with a listed phone of (512) 901-4009. NPI 1265401350 was issued on 03/14/2006.
Medicare Part D records for calendar year 2023 show 8,487 prescription claims written by this provider, covering 942 Medicare beneficiaries and totaling roughly $589K in drug spend, split 10% brand-name and 89% generic by claim count, with an opioid prescribing rate of 2.0%. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 75/100 for the 2023 performance year, 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
Provider Details
| NPI | 1265401350 |
|---|---|
| Specialty | Internal Medicine Physician |
| Credentials | DO |
| Gender | Male |
| NPI Issued | 03/14/2006 |
CMS Quality Score (MIPS)
Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.
75
Final Score
Avg: 83.1
Reporting: Individual
Hospital and facility affiliations
Facilities where William Lewis, DO 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.
The Austin Diagnostic Clinic PLLC
Austin, TX
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
Industry payments received (2024) - CMS Open Payments transparency data
The federal Physician Payments Sunshine Act (part of the Affordable Care Act) requires drug and medical-device manufacturers + group purchasing organizations to publicly report payments and other transfers of value to physicians and teaching hospitals. The data below covers 2024 for William Lewis, DO. Source: openpaymentsdata.cms.gov.
Total received
$787
Largest payer
Lilly USA, LLC
Most common payment type
Food and Beverage
Industry payments are not necessarily indicators of bias, they include research funding, consulting fees for evidence-based work, royalties for inventions, food at conferences, and similar items. The disclosure exists for transparency. Read our methodology for how we interpret this data.
License & disciplinary context - Texas TMB 2023 annual report
Aggregate state board data only, NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~77K Texas medical licensees in 2023 - they are NOT specific to William Lewis, DO. To verify William Lewis, DO's current license status, search the TMB public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
344
Total board actions, Texas 2023
Across 334 cases
4.47
Actions per 1,000 licensees
Texas statewide rate
probation
Most common action type
94 cases
TMB publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the Texas disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Brand vs generic prescribing mix · Typical
William Lewis, DO - brand share 10.0%
Internal Medicine Physician average
10% brand-name claims vs 89% generic, on 8,487 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.
8,487
Total Claims
$589K
Total Drug Cost
942
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 17,913
- Total Day Supply
- 521,312
- Brand vs Generic
- 10% brand / 89% generic
- Brand Drug Cost
- $430K
- Generic Drug Cost
- $157K
- Opioid Claims
- 168 (2.0% rate)
- Antibiotic Claims
- 301
Patient Demographics
- Average Patient Age
- 74.8 years
- Avg HCC Risk Score
- 1.07
- Gender Split
- 47% female / 53% male
- Age Distribution
- <65: 55, 65-74: 411, 75-84: 357, 85+: 119
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What William Lewis, DO prescribes most
Top Medicare Part D drugs by claim count, 2023
- Atorvastatin Calcium
Atorvastatin Calcium
424 claims
- Levothyroxine Sodium
Levothyroxine Sodium
405 claims
- Amlodipine Besylate
Amlodipine Besylate
291 claims
- Simvastatin
Simvastatin
247 claims
- Losartan Potassium
Losartan Potassium
231 claims
- Lisinopril
Lisinopril
221 claims
- Alprazolam
Alprazolam
194 claims
- Omeprazole
Omeprazole
178 claims
| Drug | Claims |
|---|---|
| Atorvastatin Calcium | 424 |
| Levothyroxine Sodium | 405 |
| Amlodipine Besylate | 291 |
| Simvastatin | 247 |
| Losartan Potassium | 231 |
| Lisinopril | 221 |
| Alprazolam | 194 |
| Omeprazole | 178 |
| Azithromycin | 177 |
| Rosuvastatin Calcium | 176 |
* 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 William Lewis, DO 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
William Lewis, DO's 8,487 claims are above the specialty average of 2,716.
Nearby Internal Medicine Physician Providers in Texas
Other clinicians with the same primary specialty enrolled in Texas, drawn from the same CMS NPPES roster as Lewis.
Dr. Muhammad A. Sattar
MD
Dallas, TX
Anunaya Aashish
Denton, TX
Dr. Queenie Ann Abad
M.D.
San Antonio, TX
Dr. Fuad Abaleka
M.D
Lubbock, TX
Dr. Carol Abalihi
M.D.
El Paso, TX
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 Texas 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.
Healthcare Guides
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Medical Specialties Explained
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Understanding Medicare Claims Data
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How insurance networks affect your costs
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Frequently Asked Questions
What is William Lewis, DO's specialty? ▼
William Lewis, DO specializes in Internal Medicine Physician and practices in Austin, Texas. Credentials: DO.
How much does William Lewis, DO prescribe under Medicare Part D? ▼
In 2023, William Lewis, DO wrote 8,487 Medicare Part D claims totaling $589K in drug costs for 942 beneficiaries.
What is William Lewis, DO's Medicare quality score? ▼
William Lewis, DO has a CMS MIPS Final Score of 75/100. The national average MIPS Final Score is 83.1. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is William Lewis, DO located? ▼
William Lewis, DO is located at 12221 N MOPAC EXPY, Austin, TX, 78758. Phone: (512) 901-4009.
What is William Lewis, DO's NPI number? ▼
William Lewis, DO's National Provider Identifier (NPI) is 1265401350, issued on 03/14/2006.
Does William Lewis, DO prescribe more brand-name or generic drugs? ▼
William Lewis, DO's prescribing is 10% brand-name and 89% generic drugs by claim count, with $430K in brand drug costs.
Does William Lewis, DO prescribe opioids? ▼
Yes, William Lewis, DO had 168 opioid claims in 2023 with an opioid prescribing rate of 2.0%.
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 William Lewis, DO prescribe most often? ▼
Based on 2023 Medicare Part D data, William Lewis, DO's most frequently prescribed drugs include Atorvastatin Calcium, Levothyroxine Sodium, Amlodipine Besylate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does William Lewis, DO accept Medicare? ▼
William Lewis, DO appears in CMS Medicare data with 8,487 Part D claims and 942 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify William Lewis, DO's credentials? ▼
William Lewis, DO's NPI is 1265401350 with credentials DO. 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
View source datasets and methodology notes
- 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
Compiled from official public sources by the PlainDoctor editorial team.