2026 NPPES data Nephrology Physician NPI 1447526066 MD
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JUSTIN CHEN, MD

Nephrology Physician in PASADENA, California. 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
780
Medicare Part D claims · 148 beneficiaries · Nephrology Physician avg: 1K
Generic prescribing
83%
generic claims · 17% brand-name · higher generic rates reduce patient out-of-pocket costs
MIPS score
44.1833/100
▼ 39 pts below national avg 83.1 · [object Object]
What the federal data reveals: JUSTIN CHEN, MD is a Nephrology Physician ([object Object]) practicing in PASADENA, California with a Medicare Part D prescribing footprint of 780 claims across 148 beneficiaries — 17% brand-name prescribing . Their CMS MIPS Final Score of 44.1833/100 (national average: 83.1) reflects performance across Quality, Cost, Interoperability, and Improvement Activities .

What stands out: JUSTIN CHEN, MD reported a CMS MIPS final score of 44.1833 out of 100, below the 83.1 national average, and filed 780 Medicare Part D claims in 2023. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

JUSTIN CHEN, MD 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).

JUSTIN CHEN, MD at a glance

Below national average

NPI registry status

Active

Issued 03/28/2012

NPI 1447526066

Primary specialty

Nephrology Physician

Mid-sized

10,534 US NPIs in this specialty

Medicare Part D claims

780 46% vs specialty avg

2023 prescription claims

Specialty avg: 1,454

MIPS final score

44.1833/100 38.91669999999999% pts

Below average band

vs 83.1 national avg

Specialty distribution in California

How Nephrology Physician compares to other specialties among California providers

California providers

Nephrology Physician share within California

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

Medicare quality performance — MIPS

JUSTIN CHEN, MD's 2023 MIPS final score plotted against the Nephrology Physician national average

Below national average
MIPS Final Score
44.1833/100
vs 83.1 national avg · 2023 performance year

MIPS final score (Nephrology Physician) — 44.1833/100 vs national avg 83.1

0%100%National avg83%44.2%
MIPS final score (Nephrology Physician) — 44.1833/100 vs national avg 83.1

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).

JUSTIN CHEN, MD is a Nephrology Physician provider practicing in PASADENA, California, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: MD. NPI: 1447526066. This profile includes practice location, specialty classification, and organizational affiliations from the CMS provider registry. Provider information is self-reported to CMS and updated monthly.

JUSTIN CHEN, MD appears in the CMS NPPES registry as a Nephrology Physician provider holding MD credentials at 301 S FAIR OAKS AVE STE 405, PASADENA, CA, 91105, with a listed phone of (626) 352-0010. NPI 1447526066 was issued on 03/28/2012. 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 780 prescription claims written by this provider, covering 148 Medicare beneficiaries and totaling roughly $246K in drug spend, split 17% brand-name and 83% 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. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 44.1833/100 for the 2023 performance year (Quality 54.2105, Cost 41.6635), compared with the national average of 83.1.

Nephrology Physician is a mid-sized specialty nationwide, with 10,534 enrolled providers across 55 states and an average of 1,454 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

301 S FAIR OAKS AVE STE 405
PASADENA, CA 91105

Provider Details

NPI 1447526066
Specialty Nephrology Physician
Credentials MD
Gender Male
NPI Issued 03/28/2012

CMS Quality Score (MIPS)

Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.

44.1833
Final Score
Avg: 83.1
54.2105
Quality
41.6635
Cost

Reporting: Individual

Hospital and facility affiliations

Facilities where JUSTIN CHEN, 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.

SEVAG BALIKIAN, M.D., A PROFESSIONAL CORPORATION
PASADENA, 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).

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 JUSTIN CHEN, MD. To verify JUSTIN CHEN, 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 · Typical

JUSTIN CHEN, MD — brand share 17.0%
Specialty average (est.)

17% brand-name claims vs 83% generic, on 780 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.

780
Total Claims
$246K
Total Drug Cost
148
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
1,696
Total Day Supply
49,508
Brand vs Generic
17% brand / 83% generic
Brand Drug Cost
$214K
Generic Drug Cost
$32K

Patient Demographics

Average Patient Age
73.3 years
Avg HCC Risk Score
5.41
Gender Split
43% female / 57% male
Age Distribution
<65: 31, 65-74: 36, 75-84: 52, 85+: 29

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Amlodipine Besylate
62
Furosemide
52
Hydralazine Hcl
44
Losartan Potassium
43
Carvedilol
34
Hydrochlorothiazide
33
Sevelamer Carbonate
30
Lisinopril
26
Lokelma
Sodium Zirconium Cyclosilicate
26
Nifedipine Er
Nifedipine
25

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

Nephrology Physician Overview

How JUSTIN CHEN, MD fits within the Nephrology Physician landscape nationally.

10,534
Nephrology Physician Providers in US
55
States with Nephrology Physician
1,454
Avg Claims per Provider

JUSTIN CHEN, MD's 780 claims are below the specialty average of 1,454.

Nearby Nephrology Physician Providers in California

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

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

Frequently Asked Questions

What is JUSTIN CHEN, MD's specialty?
JUSTIN CHEN, MD specializes in Nephrology Physician and practices in PASADENA, California. Credentials: MD.
How much does JUSTIN CHEN, MD prescribe under Medicare Part D?
In 2023, JUSTIN CHEN, MD wrote 780 Medicare Part D claims totaling $246K in drug costs for 148 beneficiaries.
What is JUSTIN CHEN, MD's Medicare quality score?
JUSTIN CHEN, MD has a CMS MIPS Final Score of 44.1833/100 (Quality: 54.2105, Cost: 41.6635). The national average MIPS Final Score is 83.1. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is JUSTIN CHEN, MD located?
JUSTIN CHEN, MD is located at 301 S FAIR OAKS AVE STE 405, PASADENA, CA, 91105. Phone: (626) 352-0010.
What is JUSTIN CHEN, MD's NPI number?
JUSTIN CHEN, MD's National Provider Identifier (NPI) is 1447526066, issued on 03/28/2012.
Does JUSTIN CHEN, MD prescribe more brand-name or generic drugs?
JUSTIN CHEN, MD's prescribing is 17% brand-name and 83% generic drugs by claim count, with $214K in brand drug costs.
How many Nephrology Physician providers are there in the US?
There are 10,534 Nephrology Physician providers across 55 states in the US. The average Nephrology Physician provider writes 1,454 Medicare Part D claims per year.
What drugs does JUSTIN CHEN, MD prescribe most often?
Based on 2023 Medicare Part D data, JUSTIN CHEN, MD's most frequently prescribed drugs include Amlodipine Besylate, Furosemide, Hydralazine Hcl. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does JUSTIN CHEN, MD accept Medicare?
JUSTIN CHEN, MD appears in CMS Medicare data with 780 Part D claims and 148 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify JUSTIN CHEN, MD's credentials?
JUSTIN CHEN, MD's NPI is 1447526066 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

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