NPI registry status
Active
2026 NPPES data Ophthalmology Physician NPI 1356831929 MD
Verify on CMS → Katherine Chuang, MD
Ophthalmology Physician in Irvine, California.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 22,082 in Ophthalmology 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
2K
Medicare Part D claims · 489 beneficiaries · Ophthalmology Physician avg: 1K
Generic prescribing
47%
generic claims · 53% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$34.46
1 payments · CMS Open Payments (Sunshine Act)
Source: CMS Medicare Part D Prescriber Public Use File, 2023
What the federal data shows
Katherine Chuang, MD filed 1,628 Medicare Part D claims in 2023 as an Ophthalmology Physician in Irvine, California, prescribing 47% generic.
- 2K
- Part D claims, 2023
- 47%
- 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.
Katherine Chuang, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
1,628 Top 18% higher than 82% 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)
Katherine Chuang, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 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 Katherine Chuang, MD?
Quality data not reportedPrimary specialty
Ophthalmology Physician
Medicare Part D claims
1,628 15% vs specialty avg
Specialty distribution in California
How Ophthalmology Physician compares to other specialties among California 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 Ophthalmology 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).
Katherine Chuang, MD appears in the CMS NPPES registry as an Ophthalmology Physician provider holding MD credentials at 850 HEALTH SCIENCES RD, Irvine, CA, 92617, with a listed phone of (949) 824-2020. NPI 1356831929 was issued on 05/18/2018.
Medicare Part D records for calendar year 2023 show 1,628 prescription claims written by this provider, covering 489 Medicare beneficiaries and totaling roughly $760K in drug spend, split 53% brand-name and 47% generic by claim count.
Ophthalmology Physician is a mid-sized specialty nationwide, with 22,082 enrolled providers across 56 states and an average of 1,420 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 | 1356831929 |
|---|---|
| Specialty | Ophthalmology Physician |
| Credentials | MD |
| Gender | Female |
| NPI Issued | 05/18/2018 |
Hospital and facility affiliations
Facilities where Katherine Chuang, 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.
Southern California Permanente Medical Group
Los Angeles, CA
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 Katherine Chuang, MD. Source: openpaymentsdata.cms.gov.
Total received
$34
Largest payer
Sight Sciences, Inc.
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 - California MBC 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 ~150K California medical licensees in 2023 - they are NOT specific to Katherine Chuang, MD. To verify Katherine Chuang, MD's current license status, search the MBC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
576
Total board actions, California 2023
Across 556 cases
3.84
Actions per 1,000 licensees
California statewide rate
probation
Most common action type
186 cases
MBC 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 California disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Brand vs generic prescribing mix · Brand-heavy
Katherine Chuang, MD - brand share 53.0%
Ophthalmology Physician average
53% brand-name claims vs 47% generic, on 1,628 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.
1,628
Total Claims
$760K
Total Drug Cost
489
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 2,345
- Total Day Supply
- 61,390
- Brand vs Generic
- 53% brand / 47% generic
- Brand Drug Cost
- $723K
- Generic Drug Cost
- $37K
- Antibiotic Claims
- 55
Patient Demographics
- Average Patient Age
- 75.5 years
- Avg HCC Risk Score
- 1.46
- Gender Split
- 63% female / 37% male
- Age Distribution
- <65: 27, 65-74: 190, 75-84: 202, 85+: 70
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Katherine Chuang, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Prednisolone Acetate
Prednisolone Acetate
399 claims
- Moxifloxacin
Moxifloxacin
182 claims
- Xiidra 101
Xiidra
101 claims
- Restasis 92
Restasis
92 claims
- Valacyclovir 71
Valacyclovir
71 claims
- Erythromycin 65
Erythromycin
65 claims
- Polymyxin B Sul-Tr… 64
Polymyxin B Sul-Trimethoprim
64 claims
- Cyclosporine 54
Cyclosporine
54 claims
| Drug | Claims |
|---|---|
| Prednisolone Acetate | 399 |
| Moxifloxacin Moxifloxacin Hcl | 182 |
| Xiidra Lifitegrast | 101 |
| Restasis Cyclosporine | 92 |
| Valacyclovir Valacyclovir Hcl | 71 |
| Erythromycin Erythromycin Base | 65 |
| Polymyxin B Sul-Trimethoprim Polymyxin B Sulf/Trimethoprim | 64 |
| Cyclosporine | 54 |
| Dorzolamide-Timolol Dorzolamide Hcl/Timolol Maleat | 48 |
| Ketorolac Tromethamine | 48 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Ophthalmology Physician Overview
How Katherine Chuang, MD fits within the Ophthalmology Physician landscape nationally.
22,082
Ophthalmology Physician Providers in US
56
States with Ophthalmology Physician
1,420
Avg Claims per Provider
Katherine Chuang, MD's 1,628 claims are above the specialty average of 1,420.
Nearby Ophthalmology Physician Providers in California
Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as Chuang.
Dr. Sam Abbassi
MD, MS
West Hills, CA
Dr. Richard Abbott
M.D.
San Francisco, CA
Dr. Nizar Abdelfattah
MD
Pasadena, CA
Dr. Parastou Abedi
MD
Aliso Viejo, CA
Dr. Shahla Abedi
MD
Aliso Viejo, CA
Compare Ophthalmology 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 California medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Ophthalmology 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 Katherine Chuang, MD's specialty? ▼
Katherine Chuang, MD specializes in Ophthalmology Physician and practices in Irvine, California. Credentials: MD.
How much does Katherine Chuang, MD prescribe under Medicare Part D? ▼
In 2023, Katherine Chuang, MD wrote 1,628 Medicare Part D claims totaling $760K in drug costs for 489 beneficiaries.
Where is Katherine Chuang, MD located? ▼
Katherine Chuang, MD is located at 850 HEALTH SCIENCES RD, Irvine, CA, 92617. Phone: (949) 824-2020.
What is Katherine Chuang, MD's NPI number? ▼
Katherine Chuang, MD's National Provider Identifier (NPI) is 1356831929, issued on 05/18/2018.
Does Katherine Chuang, MD prescribe more brand-name or generic drugs? ▼
Katherine Chuang, MD's prescribing is 53% brand-name and 47% generic drugs by claim count, with $723K in brand drug costs.
How many Ophthalmology Physician providers are there in the US? ▼
There are 22,082 Ophthalmology Physician providers across 56 states in the US. The average Ophthalmology Physician provider writes 1,420 Medicare Part D claims per year.
What drugs does Katherine Chuang, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, Katherine Chuang, MD's most frequently prescribed drugs include Prednisolone Acetate, Moxifloxacin, Xiidra. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Katherine Chuang, MD accept Medicare? ▼
Katherine Chuang, MD appears in CMS Medicare data with 1,628 Part D claims and 489 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Katherine Chuang, MD's credentials? ▼
Katherine Chuang, MD's NPI is 1356831929 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
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.