2026 NPPES data Critical Care Medicine (Internal Medicine) Physician NPI 1457848996 MD
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RUOYING FENG, MD

Critical Care Medicine (Internal Medicine) Physician in LOMA LINDA, 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
66
Medicare Part D claims · 22 beneficiaries · Critical Care Medicine (Internal Medicine) Physician avg: 1K
Generic prescribing
47%
generic claims · 53% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

RUOYING FENG, MD filed 66 Medicare Part D claims in 2023 as a Critical Care Medicine (Internal Medicine) Physician in LOMA LINDA, California, prescribing 47% generic.

66
Part D claims, 2023
47%
generic prescribing

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.

RUOYING FENG, MD's Medicare Part D volume vs every U.S. prescriber

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

66 0th percentile higher than 0% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). This entry sits in this band. 200–400: 182,923 prescribers (13%). Above this entry. 400–600: 90,619 prescribers (7%). Above this entry. 600–800: 56,224 prescribers (4%). Above this entry. 800–1,000: 40,919 prescribers (3%). Above this entry. 1,000–1,200: 31,827 prescribers (2%). Above this entry. 1,200–1,400: 26,224 prescribers (2%). Above this entry. 1,400–1,600: 21,710 prescribers (2%). Above this entry. 1,600–1,800: 19,072 prescribers (1%). Above this entry. 1,800–2,000: 16,451 prescribers (1%). Above this entry. 2,000–2,200: 213,991 prescribers (16%). Above this entry. 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-eligible specialty (heuristic — not verified)

RUOYING FENG, MD practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).

What does the federal data show about RUOYING FENG, MD?

Quality data not reported

NPI registry status

Active

Issued 04/19/2018

NPI 1457848996

Primary specialty

Critical Care Medicine (Internal Medicine) Physician

Mid-sized

6,631 US NPIs in this specialty

Medicare Part D claims

66 94% vs specialty avg

2023 prescription claims

Specialty avg: 1,069

Specialty distribution in California

How Critical Care Medicine (Internal Medicine) Physician compares to other specialties among California providers

California providers

Critical Care Medicine (Internal Medicine) Physician share within California

1. Critical Care Medicine (Internal Medicine) Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Critical Care Medicine (Internal Medicine) Physician share within California

Specialty board-certification context

Estimated specialty board-certified rate — Critical Care Medicine (Internal Medicine) Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Critical Care Medicine (Internal Medicine) Physician ABMS/AOA estimate

Est. board-certified rate (Critical Care Medicine (Internal Medicine) Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Critical Care Medicine (Internal Medicine) 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).

RUOYING FENG, MD appears in the CMS NPPES registry as a Critical Care Medicine (Internal Medicine) Physician provider holding MD credentials at 11201 BENTON ST, LOMA LINDA, CA, 92357, with a listed phone of (858) 353-6887. NPI 1457848996 was issued on 04/19/2018. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what FENG 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 66 prescription claims written by this provider, covering 22 Medicare beneficiaries and totaling roughly $20K in drug spend, split 53% brand-name and 47% 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.

Critical Care Medicine (Internal Medicine) Physician is a mid-sized specialty nationwide, with 6,631 enrolled providers across 53 states and an average of 1,069 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

11201 BENTON ST
LOMA LINDA, CA 92357

Provider Details

NPI 1457848996
Specialty Critical Care Medicine (Internal Medicine) Physician
Credentials MD
Gender Female
NPI Issued 04/19/2018

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 RUOYING FENG, MD. To verify RUOYING FENG, 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

RUOYING FENG, MD — brand share 53.0%
Specialty average (est.)

53% brand-name claims vs 47% generic, on 66 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.

66
Total Claims
$20K
Total Drug Cost
22
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
85
Total Day Supply
2,356
Brand vs Generic
53% brand / 47% generic
Brand Drug Cost
$19K
Generic Drug Cost
$962

Patient Demographics

Average Patient Age
75.6 years
Avg HCC Risk Score
2.39

Critical Care Medicine (Internal Medicine) Physician Overview

How RUOYING FENG, MD fits within the Critical Care Medicine (Internal Medicine) Physician landscape nationally.

6,631
Critical Care Medicine (Internal Medicine) Physician Providers in US
53
States with Critical Care Medicine (Internal Medicine) Physician
1,069
Avg Claims per Provider

RUOYING FENG, MD's 66 claims are below the specialty average of 1,069.

Nearby Critical Care Medicine (Internal Medicine) Physician Providers in California

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

Compare Critical Care Medicine (Internal Medicine) Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is RUOYING FENG, MD's specialty?
RUOYING FENG, MD specializes in Critical Care Medicine (Internal Medicine) Physician and practices in LOMA LINDA, California. Credentials: MD.
How much does RUOYING FENG, MD prescribe under Medicare Part D?
In 2023, RUOYING FENG, MD wrote 66 Medicare Part D claims totaling $20K in drug costs for 22 beneficiaries.
Where is RUOYING FENG, MD located?
RUOYING FENG, MD is located at 11201 BENTON ST, LOMA LINDA, CA, 92357. Phone: (858) 353-6887.
What is RUOYING FENG, MD's NPI number?
RUOYING FENG, MD's National Provider Identifier (NPI) is 1457848996, issued on 04/19/2018.
Does RUOYING FENG, MD prescribe more brand-name or generic drugs?
RUOYING FENG, MD's prescribing is 53% brand-name and 47% generic drugs by claim count, with $19K in brand drug costs.
How many Critical Care Medicine (Internal Medicine) Physician providers are there in the US?
There are 6,631 Critical Care Medicine (Internal Medicine) Physician providers across 53 states in the US. The average Critical Care Medicine (Internal Medicine) Physician provider writes 1,069 Medicare Part D claims per year.
Does RUOYING FENG, MD accept Medicare?
RUOYING FENG, MD appears in CMS Medicare data with 66 Part D claims and 22 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify RUOYING FENG, MD's credentials?
RUOYING FENG, MD's NPI is 1457848996 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