2026 NPPES data Ophthalmology Physician NPI 1376076018 MD, MPHIL
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KAREN CHEN, MD, MPHIL

Ophthalmology Physician in HONOLULU, Hawaii. 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
2K
Medicare Part D claims · 602 beneficiaries · Ophthalmology Physician avg: 1K
Generic prescribing
77%
generic claims · 23% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$584.94
10 payments · CMS Open Payments (Sunshine Act)

What the federal data shows

KAREN CHEN, MD, MPHIL filed 2,133 Medicare Part D claims in 2023 as a Ophthalmology Physician in HONOLULU, Hawaii, prescribing 77% generic.

2K
Part D claims, 2023
77%
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.

KAREN CHEN, MD, MPHIL's Medicare Part D volume vs every U.S. prescriber

Total Medicare Part D claims, 2023 — across all CMS prescribers nationally

2,133 Top 15% higher than 85% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). Below this entry. 400–600: 90,619 prescribers (7%). Below this entry. 600–800: 56,224 prescribers (4%). Below this entry. 800–1,000: 40,919 prescribers (3%). Below this entry. 1,000–1,200: 31,827 prescribers (2%). Below this entry. 1,200–1,400: 26,224 prescribers (2%). Below this entry. 1,400–1,600: 21,710 prescribers (2%). Below this entry. 1,600–1,800: 19,072 prescribers (1%). Below this entry. 1,800–2,000: 16,451 prescribers (1%). Below this entry. 2,000–2,200: 213,991 prescribers (16%). This entry sits in this band. This provider 0 2K+ every Part D prescriber (claims/yr), bucketed by value

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)

KAREN CHEN, MD, MPHIL 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 KAREN CHEN, MD, MPHIL?

Quality data not reported

NPI registry status

Active

Issued 04/10/2017

NPI 1376076018

Primary specialty

Ophthalmology Physician

Mid-sized

22,090 US NPIs in this specialty

Medicare Part D claims

2,133 50% vs specialty avg

2023 prescription claims

Specialty avg: 1,420

Specialty distribution in Hawaii

How Ophthalmology Physician compares to other specialties among Hawaii providers

Hawaii providers

Ophthalmology Physician share within Hawaii

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

Specialty board-certification context

Estimated specialty board-certified rate — Ophthalmology Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Ophthalmology Physician ABMS/AOA estimate

Est. board-certified rate (Ophthalmology Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Ophthalmology Physician) — ABMS / AOA estimate

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).

KAREN CHEN, MD, MPHIL appears in the CMS NPPES registry as a Ophthalmology Physician provider holding MD, MPHIL credentials at 1010 PENSACOLA ST, HONOLULU, HI, 96814, with a listed phone of (808) 432-2000. NPI 1376076018 was issued on 04/10/2017. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what CHEN 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 2,133 prescription claims written by this provider, covering 602 Medicare beneficiaries and totaling roughly $163K in drug spend, split 23% brand-name and 77% 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.

Ophthalmology Physician is a mid-sized specialty nationwide, with 22,090 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

1010 PENSACOLA ST
HONOLULU, HI 96814

Provider Details

NPI 1376076018
Specialty Ophthalmology Physician
Credentials MD, MPHIL
Gender Female
NPI Issued 04/10/2017

Hospital and facility affiliations

Facilities where KAREN CHEN, MD, MPHIL 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.

PERMANENTE MEDICAL GROUP INC
SAN FRANCISCO, 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 KAREN CHEN, MD, MPHIL. Source: openpaymentsdata.cms.gov.

Total received

$585

Largest payer

ABBVIE 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.

Brand vs generic prescribing mix · Typical

KAREN CHEN, MD, MPHIL — brand share 23.0%
Specialty average (est.)

23% brand-name claims vs 77% generic, on 2,133 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.

2,133
Total Claims
$163K
Total Drug Cost
602
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
4,086
Total Day Supply
117,285
Brand vs Generic
23% brand / 77% generic
Brand Drug Cost
$116K
Generic Drug Cost
$47K

Patient Demographics

Average Patient Age
78.6 years
Avg HCC Risk Score
1.17
Gender Split
50% female / 50% male

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

What KAREN CHEN, MD, MPHIL 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
Latanoprost
412
Dorzolamide-Timolol
Dorzolamide Hcl/Timolol Maleat
368
Prednisolone Acetate
263
Diclofenac Sodium
218
Timolol Maleate
200
Brimonidine Tartrate
199
Rhopressa
Netarsudil Mesylate
142
Moxifloxacin
Moxifloxacin Hcl
54
Dorzolamide Hcl
50

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

Ophthalmology Physician Overview

How KAREN CHEN, MD, MPHIL fits within the Ophthalmology Physician landscape nationally.

22,090
Ophthalmology Physician Providers in US
56
States with Ophthalmology Physician
1,420
Avg Claims per Provider

KAREN CHEN, MD, MPHIL's 2,133 claims are above the specialty average of 1,420.

Nearby Ophthalmology Physician Providers in Hawaii

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

Compare Ophthalmology Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is KAREN CHEN, MD, MPHIL's specialty?
KAREN CHEN, MD, MPHIL specializes in Ophthalmology Physician and practices in HONOLULU, Hawaii. Credentials: MD, MPHIL.
How much does KAREN CHEN, MD, MPHIL prescribe under Medicare Part D?
In 2023, KAREN CHEN, MD, MPHIL wrote 2,133 Medicare Part D claims totaling $163K in drug costs for 602 beneficiaries.
Where is KAREN CHEN, MD, MPHIL located?
KAREN CHEN, MD, MPHIL is located at 1010 PENSACOLA ST, HONOLULU, HI, 96814. Phone: (808) 432-2000.
What is KAREN CHEN, MD, MPHIL's NPI number?
KAREN CHEN, MD, MPHIL's National Provider Identifier (NPI) is 1376076018, issued on 04/10/2017.
Does KAREN CHEN, MD, MPHIL prescribe more brand-name or generic drugs?
KAREN CHEN, MD, MPHIL's prescribing is 23% brand-name and 77% generic drugs by claim count, with $116K in brand drug costs.
How many Ophthalmology Physician providers are there in the US?
There are 22,090 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 KAREN CHEN, MD, MPHIL prescribe most often?
Based on 2023 Medicare Part D data, KAREN CHEN, MD, MPHIL's most frequently prescribed drugs include Latanoprost, Dorzolamide-Timolol, Prednisolone Acetate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does KAREN CHEN, MD, MPHIL accept Medicare?
KAREN CHEN, MD, MPHIL appears in CMS Medicare data with 2,133 Part D claims and 602 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify KAREN CHEN, MD, MPHIL's credentials?
KAREN CHEN, MD, MPHIL's NPI is 1376076018 with credentials MD, MPHIL. 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.
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