NPI registry status
Active
2026 NPPES data Critical Care Medicine (Internal Medicine) Physician NPI 1629084579 MD
Verify on CMS → Shih-Wen Chang, MD
Critical Care Medicine (Internal Medicine) Physician in West Allis, Wisconsin.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 6,646 in Critical Care Medicine (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
1K
Medicare Part D claims · 210 beneficiaries · Critical Care Medicine (Internal Medicine) Physician avg: 1K
Generic prescribing
0%
generic claims · 64% brand-name · higher generic rates reduce patient out-of-pocket costs
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
Shih-Wen Chang, MD filed 1,323 Medicare Part D claims in 2023 as a Critical Care Medicine (Internal Medicine) Physician in West Allis, Wisconsin, prescribing 0% generic.
- 1K
- Part D claims, 2023
- 0%
- 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.
Shih-Wen Chang, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
1,323 Top 21% higher than 79% of 1,370,886 prescribers
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 certification likely (heuristic, not verified)
Shih-Wen Chang, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 6 hospital affiliations - 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 Shih-Wen Chang, MD?
Quality data not reportedPrimary specialty
Critical Care Medicine (Internal Medicine) Physician
Medicare Part D claims
1,323 24% vs specialty avg
Specialty distribution in Wisconsin
How Critical Care Medicine (Internal Medicine) Physician compares to other specialties among Wisconsin providers
Board certification
Not published by CMS
CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Critical Care Medicine (Internal Medicine) Physician. Verify directly:
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).
Shih-Wen Chang, MD appears in the CMS NPPES registry as a Critical Care Medicine (Internal Medicine) Physician provider holding MD credentials at 2424 S 90TH ST FL 3, West Allis, WI, 53227, with a listed phone of (414) 328-8150. NPI 1629084579 was issued on 07/31/2006.
Medicare Part D records for calendar year 2023 show 1,323 prescription claims written by this provider, covering 210 Medicare beneficiaries and totaling roughly $598K in drug spend, split 64% brand-name and 0% generic by claim count.
Critical Care Medicine (Internal Medicine) Physician is a mid-sized specialty nationwide, with 6,646 enrolled providers across 53 states and an average of 1,069 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 | 1629084579 |
|---|---|
| Specialty | Critical Care Medicine (Internal Medicine) Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 07/31/2006 |
Hospital and facility affiliations
Facilities where Shih-Wen Chang, MD 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.
According to CMS billing records, Shih-Wen Chang, MD is affiliated with 6 Medicare-billing facilities across 2 states.
Ascension Medical Group-Fox Valley Wisconsin Inc
Appleton, WI
Aspirus Wausau Hospital Inc
Wausau, WI
Aurora Medical Group, Inc.
West Allis, WI
Carle Health Care Incorporated
Peoria, IL
Dean Health Systems Inc
Madison, WI
Methodist Medical Center OF Illinois
Peoria, IL
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 · Brand-heavy
Shih-Wen Chang, MD - brand share 64.0%
Critical Care Medicine (Internal Medicine) Physician average
64% brand-name claims vs 0% generic, on 1,323 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.
1,323
Total Claims
$598K
Total Drug Cost
210
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 1,936
- Total Day Supply
- 51,769
- Brand vs Generic
- 64% brand / 0% generic
- Brand Drug Cost
- $566K
- Antibiotic Claims
- 195
Patient Demographics
- Average Patient Age
- 73.3 years
- Avg HCC Risk Score
- 1.76
- Gender Split
- 64% female / 36% male
- Age Distribution
- <65: 28, 65-74: 87, 75-84: 73, 85+: 22
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Shih-Wen Chang, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Albuterol Sulfate …
Albuterol Sulfate Hfa
152 claims
- Trelegy Ellipta
Trelegy Ellipta
141 claims
- Azithromycin
Azithromycin
115 claims
- Symbicort
Symbicort
112 claims
- Advair Diskus
Advair Diskus
99 claims
- Prednisone
Prednisone
94 claims
- Ventolin Hfa
Ventolin Hfa
66 claims
- Breo Ellipta 54
Breo Ellipta
54 claims
| Drug | Claims |
|---|---|
| Albuterol Sulfate Hfa Albuterol Sulfate | 152 |
| Trelegy Ellipta Fluticasone/Umeclidin/Vilanter | 141 |
| Azithromycin | 115 |
| Symbicort Budesonide/Formoterol Fumarate | 112 |
| Advair Diskus Fluticasone Propion/Salmeterol | 99 |
| Prednisone | 94 |
| Ventolin Hfa Albuterol Sulfate | 66 |
| Breo Ellipta Fluticasone/Vilanterol | 54 |
| Flovent Hfa Fluticasone Propionate | 46 |
| Fluticasone-Salmeterol Fluticasone Propion/Salmeterol | 39 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
More Critical Care Medicine (Internal Medicine) Physician in WI →
All providers in Wisconsin →
Compare specialties →
Critical Care Medicine (Internal Medicine) Physician Overview
How Shih-Wen Chang, MD fits within the Critical Care Medicine (Internal Medicine) Physician landscape nationally.
6,646
Critical Care Medicine (Internal Medicine) Physician Providers in US
53
States with Critical Care Medicine (Internal Medicine) Physician
1,069
Avg Claims per Provider
Shih-Wen Chang, MD's 1,323 claims are above the specialty average of 1,069.
Nearby Critical Care Medicine (Internal Medicine) Physician Providers in Wisconsin
Other clinicians with the same primary specialty enrolled in Wisconsin, drawn from the same CMS NPPES roster as Chang.
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 Wisconsin medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Critical Care Medicine (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.
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Frequently Asked Questions
What is Shih-Wen Chang, MD's specialty? ▼
Shih-Wen Chang, MD specializes in Critical Care Medicine (Internal Medicine) Physician and practices in West Allis, Wisconsin. Credentials: MD.
How much does Shih-Wen Chang, MD prescribe under Medicare Part D? ▼
In 2023, Shih-Wen Chang, MD wrote 1,323 Medicare Part D claims totaling $598K in drug costs for 210 beneficiaries.
Where is Shih-Wen Chang, MD located? ▼
Shih-Wen Chang, MD is located at 2424 S 90TH ST FL 3, West Allis, WI, 53227. Phone: (414) 328-8150.
What is Shih-Wen Chang, MD's NPI number? ▼
Shih-Wen Chang, MD's National Provider Identifier (NPI) is 1629084579, issued on 07/31/2006.
Does Shih-Wen Chang, MD prescribe more brand-name or generic drugs? ▼
Shih-Wen Chang, MD's prescribing is 64% brand-name and 0% generic drugs by claim count, with $566K in brand drug costs.
How many Critical Care Medicine (Internal Medicine) Physician providers are there in the US? ▼
There are 6,646 Critical Care Medicine (Internal Medicine) Physician providers across 53 states in the US. The average Critical Care Medicine (Internal Medicine) Physician provider writes 1,069 Medicare Part D claims per year.
What drugs does Shih-Wen Chang, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, Shih-Wen Chang, MD's most frequently prescribed drugs include Albuterol Sulfate Hfa, Trelegy Ellipta, Azithromycin. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Shih-Wen Chang, MD accept Medicare? ▼
Shih-Wen Chang, MD appears in CMS Medicare data with 1,323 Part D claims and 210 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Shih-Wen Chang, MD's credentials? ▼
Shih-Wen Chang, MD's NPI is 1629084579 with credentials MD. 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.
- 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.
Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of May 2026.