2026 NPPES data Nephrology Physician NPI 1962502872 MD
Verify on CMS →

RANDOLPH CHEN, MD

Nephrology Physician in BELMONT, 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
2K
Medicare Part D claims · 352 beneficiaries · Nephrology Physician avg: 1K
Generic prescribing
92%
generic claims · 8% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$5.6K
45 payments · CMS Open Payments (Sunshine Act)
What the federal data reveals: RANDOLPH CHEN, MD is a Nephrology Physician ([object Object]) practicing in BELMONT, California with a Medicare Part D prescribing footprint of 2K claims across 352 beneficiaries — 8% brand-name prescribing . Industry payments of $5.6K across 45 transactions are disclosed under CMS Open Payments (Sunshine Act).

What stands out: RANDOLPH CHEN, MD filed 2,098 Medicare Part D claims in 2023 across BELMONT, California. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

RANDOLPH CHEN, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 2 hospital affiliations — signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).

RANDOLPH CHEN, MD at a glance

Quality data not reported

NPI registry status

Active

Issued 09/22/2006

NPI 1962502872

Primary specialty

Nephrology Physician

Mid-sized

10,534 US NPIs in this specialty

Medicare Part D claims

2,098 44% vs specialty avg

2023 prescription claims

Specialty avg: 1,454

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

Specialty board-certification context

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

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

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

0%100%78%
Est. board-certified rate (Nephrology 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).

RANDOLPH CHEN, MD is a Nephrology Physician provider practicing in BELMONT, California, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: MD. NPI: 1962502872. 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.

RANDOLPH CHEN, MD appears in the CMS NPPES registry as a Nephrology Physician provider holding MD credentials at 1301 SHOREWAY RD, BELMONT, CA, 94002, with a listed phone of (650) 596-7000. NPI 1962502872 was issued on 09/22/2006. 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 2,098 prescription claims written by this provider, covering 352 Medicare beneficiaries and totaling roughly $213K in drug spend, split 8% brand-name and 92% 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.

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

1301 SHOREWAY RD
BELMONT, CA 94002

Provider Details

NPI 1962502872
Specialty Nephrology Physician
Credentials MD
Gender Male
NPI Issued 09/22/2006

Hospital and facility affiliations

Facilities where RANDOLPH 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.

COUNTY OF SAN MATEO
SAN MATEO, CA
SAN MATEO DIALYSIS ASSOCIATES
BURLINGAME, 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 RANDOLPH CHEN, MD. Source: openpaymentsdata.cms.gov.

Total received

$5.6K

Largest payer

Fresenius USA Marketing, 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 RANDOLPH CHEN, MD. To verify RANDOLPH 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 · Generic-heavy

RANDOLPH CHEN, MD — brand share 8.0%
Specialty average (est.)

8% brand-name claims vs 92% generic, on 2,098 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.

2,098
Total Claims
$213K
Total Drug Cost
352
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
5,492
Total Day Supply
163,334
Brand vs Generic
8% brand / 92% generic
Brand Drug Cost
$129K
Generic Drug Cost
$84K

Patient Demographics

Average Patient Age
78.1 years
Avg HCC Risk Score
2.97
Gender Split
42% female / 58% male
Age Distribution
<65: 22, 65-74: 87, 75-84: 153, 85+: 90

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Losartan Potassium
320
Amlodipine Besylate
215
Doxazosin Mesylate
166
Metoprolol Succinate
166
Calcitriol
118
Furosemide
106
Chlorthalidone
90
Hydrochlorothiazide
71
Hydralazine Hcl
68
Allopurinol
64

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

Nephrology Physician Overview

How RANDOLPH 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

RANDOLPH CHEN, MD's 2,098 claims are above 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 RANDOLPH CHEN, MD's specialty?
RANDOLPH CHEN, MD specializes in Nephrology Physician and practices in BELMONT, California. Credentials: MD.
How much does RANDOLPH CHEN, MD prescribe under Medicare Part D?
In 2023, RANDOLPH CHEN, MD wrote 2,098 Medicare Part D claims totaling $213K in drug costs for 352 beneficiaries.
Where is RANDOLPH CHEN, MD located?
RANDOLPH CHEN, MD is located at 1301 SHOREWAY RD, BELMONT, CA, 94002. Phone: (650) 596-7000.
What is RANDOLPH CHEN, MD's NPI number?
RANDOLPH CHEN, MD's National Provider Identifier (NPI) is 1962502872, issued on 09/22/2006.
Does RANDOLPH CHEN, MD prescribe more brand-name or generic drugs?
RANDOLPH CHEN, MD's prescribing is 8% brand-name and 92% generic drugs by claim count, with $129K 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 RANDOLPH CHEN, MD prescribe most often?
Based on 2023 Medicare Part D data, RANDOLPH CHEN, MD's most frequently prescribed drugs include Losartan Potassium, Amlodipine Besylate, Doxazosin Mesylate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does RANDOLPH CHEN, MD accept Medicare?
RANDOLPH CHEN, MD appears in CMS Medicare data with 2,098 Part D claims and 352 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify RANDOLPH CHEN, MD's credentials?
RANDOLPH CHEN, MD's NPI is 1962502872 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.
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