NPI registry status
Active
2026 NPPES data Ophthalmology Physician NPI 1730689340 MD
Verify on CMS → Aimee Chang, MD
Ophthalmology Physician in Freedom, 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
3K
Medicare Part D claims · 896 beneficiaries · Ophthalmology Physician avg: 1K
Generic prescribing
66%
generic claims · 34% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$883.53
26 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
Aimee Chang, MD filed 2,888 Medicare Part D claims in 2023 as a Ophthalmology Physician in Freedom, California, prescribing 66% generic.
- 3K
- Part D claims, 2023
- 66%
- 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.
Aimee Chang, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
2,888 Top 12% higher than 88% 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)
Aimee Chang, 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 Aimee Chang, MD?
Quality data not reportedPrimary specialty
Ophthalmology Physician
Medicare Part D claims
2,888 103% 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).
Aimee Chang, MD appears in the CMS NPPES registry as an Ophthalmology Physician provider holding MD credentials at 160 GREEN VALLEY RD STE 202, Freedom, CA, 95019, with a listed phone of (831) 728-2020. NPI 1730689340 was issued on 02/20/2018.
Medicare Part D records for calendar year 2023 show 2,888 prescription claims written by this provider, covering 896 Medicare beneficiaries and totaling roughly $358K in drug spend, split 34% brand-name and 66% 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 | 1730689340 |
|---|---|
| Specialty | Ophthalmology Physician |
| Credentials | MD |
| Gender | Female |
| NPI Issued | 02/20/2018 |
Hospital and facility affiliations
Facilities where Aimee 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.
Spectrum Eye Physicians A Medical Corporation
Santa Cruz, 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 Aimee Chang, MD. Source: openpaymentsdata.cms.gov.
Total received
$884
Largest payer
Alcon Vision 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 - 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 Aimee Chang, MD. To verify Aimee Chang, 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 · Above average
Aimee Chang, MD - brand share 34.0%
Ophthalmology Physician average
34% brand-name claims vs 66% generic, on 2,888 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.
2,888
Total Claims
$358K
Total Drug Cost
896
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 5,552
- Total Day Supply
- 160,090
- Brand vs Generic
- 34% brand / 66% generic
- Brand Drug Cost
- $270K
- Generic Drug Cost
- $88K
Patient Demographics
- Average Patient Age
- 75.6 years
- Avg HCC Risk Score
- 1.18
- Gender Split
- 57% female / 43% male
- Age Distribution
- <65: 59, 65-74: 350, 75-84: 353, 85+: 134
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Aimee Chang, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Latanoprost
Latanoprost
729 claims
- Brimonidine Tartrate
Brimonidine Tartrate
337 claims
- Dorzolamide-Timolol
Dorzolamide-Timolol
336 claims
- Timolol Maleate 237
Timolol Maleate
237 claims
- Prednisolone Acetate 199
Prednisolone Acetate
199 claims
- Rhopressa 131
Rhopressa
131 claims
- Dorzolamide Hcl 105
Dorzolamide Hcl
105 claims
- Lumigan 71
Lumigan
71 claims
| Drug | Claims |
|---|---|
| Latanoprost | 729 |
| Brimonidine Tartrate | 337 |
| Dorzolamide-Timolol Dorzolamide Hcl/Timolol Maleat | 336 |
| Timolol Maleate | 237 |
| Prednisolone Acetate | 199 |
| Rhopressa Netarsudil Mesylate | 131 |
| Dorzolamide Hcl | 105 |
| Lumigan Bimatoprost | 71 |
| Moxifloxacin Moxifloxacin Hcl | 66 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Ophthalmology Physician Overview
How Aimee Chang, 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
Aimee Chang, MD's 2,888 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 Chang.
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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Understanding Medicare Claims Data
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How insurance networks affect your costs
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Frequently Asked Questions
What is Aimee Chang, MD's specialty? ▼
Aimee Chang, MD specializes in Ophthalmology Physician and practices in Freedom, California. Credentials: MD.
How much does Aimee Chang, MD prescribe under Medicare Part D? ▼
In 2023, Aimee Chang, MD wrote 2,888 Medicare Part D claims totaling $358K in drug costs for 896 beneficiaries.
Where is Aimee Chang, MD located? ▼
Aimee Chang, MD is located at 160 GREEN VALLEY RD STE 202, Freedom, CA, 95019. Phone: (831) 728-2020.
What is Aimee Chang, MD's NPI number? ▼
Aimee Chang, MD's National Provider Identifier (NPI) is 1730689340, issued on 02/20/2018.
Does Aimee Chang, MD prescribe more brand-name or generic drugs? ▼
Aimee Chang, MD's prescribing is 34% brand-name and 66% generic drugs by claim count, with $270K 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 Aimee Chang, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, Aimee Chang, MD's most frequently prescribed drugs include Latanoprost, Brimonidine Tartrate, Dorzolamide-Timolol. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Aimee Chang, MD accept Medicare? ▼
Aimee Chang, MD appears in CMS Medicare data with 2,888 Part D claims and 896 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Aimee Chang, MD's credentials? ▼
Aimee Chang, MD's NPI is 1730689340 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.