2026 NPPES data Hematology (Internal Medicine) Physician NPI 1417047283 M.D.
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Leroy Wayne Keiser, M.D.

Hematology (Internal Medicine) Physician in Santa Rosa, 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 1,451 in Hematology (Internal Medicine) 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
1K
Medicare Part D claims · 328 beneficiaries · Hematology (Internal Medicine) Physician avg: 693
Industry payments
$16.8K
16 payments · CMS Open Payments (Sunshine Act)
Compiled from official public sources by the PlainDoctor editorial team.

What the federal data shows

Leroy Wayne Keiser, M.D. filed 1,344 Medicare Part D claims in 2023 as a Hematology (Internal Medicine) Physician in Santa Rosa, California.

1K
Part D claims, 2023
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.

Leroy Wayne Keiser, M.D.'s Medicare Part D volume vs every U.S. prescriber

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

1,344 Top 21% higher than 79% 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%). This entry sits in this band. 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. 2K+: 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 certification likely (heuristic, not verified)

Leroy Wayne Keiser, M.D. 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 Leroy Wayne Keiser, M.D.?

Quality data not reported

NPI registry status

Active

Issued 10/13/2006

NPI 1417047283

Primary specialty

Hematology (Internal Medicine) Physician

Niche

1,451 US NPIs in this specialty

Medicare Part D claims

1,344 94% vs specialty avg

2023 prescription claims

Specialty avg: 693

Specialty distribution in California

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

California providers
Behavior Technician - 17.3%Behavior Technician17.3%Marriage & Family Therapist - 5.5%Marriage & Family Therapist5.5%Student in an Organized Health Care Education/Training Program - 5%Student in an Organized Health Care Education/Training Program5%Mental Health Counselor - 3.9%Mental Health Counselor3.9%Pharmacist - 3.5%Pharmacist3.5%Clinical Social Worker - 3.1%Clinical Social Worker3.1%Hematology (Internal Medicine) Physician - 0%Hematology (Internal Medicine) Physician0%
Largest specialties in California (% of in-state 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 Hematology (Internal Medicine) 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).

Leroy Wayne Keiser, M.D. appears in the CMS NPPES registry as a Hematology (Internal Medicine) Physician provider holding M.D. credentials at 3555 ROUND BARN CIR STE 100, Santa Rosa, CA, 95403, with a listed phone of (707) 528-1050. NPI 1417047283 was issued on 10/13/2006.

Medicare Part D records for calendar year 2023 show 1,344 prescription claims written by this provider, covering 328 Medicare beneficiaries and totaling roughly $3.8 million in drug spend, with an opioid prescribing rate of 8.1%.

Hematology (Internal Medicine) Physician is a narrow specialty nationwide, with 1,451 enrolled providers across 50 states and an average of 693 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

3555 ROUND BARN CIR STE 100
Santa Rosa, CA 95403

Provider Details

NPI 1417047283
Specialty Hematology (Internal Medicine) Physician
Credentials M.D.
Gender Male
NPI Issued 10/13/2006

Hospital and facility affiliations

Facilities where Leroy Wayne Keiser, M.D. 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.

Providence Medical Foundation
Petaluma, 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 Leroy Wayne Keiser, M.D.. Source: openpaymentsdata.cms.gov.

Total received

$16.8K

Largest payer

Amgen Inc.

Most common payment type

Compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program

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 Leroy Wayne Keiser, M.D.. To verify Leroy Wayne Keiser, M.D.'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.

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

1,344
Total Claims
$3.8M
Total Drug Cost
328
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
1,903
Total Day Supply
50,982
Generic Drug Cost
$362K
Opioid Claims
109 (8.1% rate)
Antibiotic Claims
34

Patient Demographics

Average Patient Age
75.6 years
Avg HCC Risk Score
2.11
Gender Split
60% female / 40% male
Age Distribution
<65: 21, 65-74: 121, 75-84: 143, 85+: 43

Top Prescribed Drugs (Medicare Part D)

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

What Leroy Wayne Keiser, M.D. 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
Eliquis
Apixaban
125
Prednisone
74
Letrozole
69
Potassium Chloride
53
Gabapentin
47
Dexamethasone
40
Abiraterone Acetate
39
Anastrozole
38
Hydrocodone-Acetaminophen
Hydrocodone/Acetaminophen
38
Levothyroxine Sodium
37

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

Hematology (Internal Medicine) Physician Overview

How Leroy Wayne Keiser, M.D. fits within the Hematology (Internal Medicine) Physician landscape nationally.

1,451
Hematology (Internal Medicine) Physician Providers in US
50
States with Hematology (Internal Medicine) Physician
693
Avg Claims per Provider

Leroy Wayne Keiser, M.D.'s 1,344 claims are above the specialty average of 693.

Nearby Hematology (Internal Medicine) Physician Providers in California

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

Compare Hematology (Internal Medicine) 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 Hematology (Internal Medicine) 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.

Frequently Asked Questions

What is Leroy Wayne Keiser, M.D.'s specialty?
Leroy Wayne Keiser, M.D. specializes in Hematology (Internal Medicine) Physician and practices in Santa Rosa, California. Credentials: M.D..
How much does Leroy Wayne Keiser, M.D. prescribe under Medicare Part D?
In 2023, Leroy Wayne Keiser, M.D. wrote 1,344 Medicare Part D claims totaling $3.8M in drug costs for 328 beneficiaries.
Where is Leroy Wayne Keiser, M.D. located?
Leroy Wayne Keiser, M.D. is located at 3555 ROUND BARN CIR STE 100, Santa Rosa, CA, 95403. Phone: (707) 528-1050.
What is Leroy Wayne Keiser, M.D.'s NPI number?
Leroy Wayne Keiser, M.D.'s National Provider Identifier (NPI) is 1417047283, issued on 10/13/2006.
Does Leroy Wayne Keiser, M.D. prescribe opioids?
Yes, Leroy Wayne Keiser, M.D. had 109 opioid claims in 2023 with an opioid prescribing rate of 8.1%.
How many Hematology (Internal Medicine) Physician providers are there in the US?
There are 1,451 Hematology (Internal Medicine) Physician providers across 50 states in the US. The average Hematology (Internal Medicine) Physician provider writes 693 Medicare Part D claims per year.
What drugs does Leroy Wayne Keiser, M.D. prescribe most often?
Based on 2023 Medicare Part D data, Leroy Wayne Keiser, M.D.'s most frequently prescribed drugs include Eliquis, Prednisone, Letrozole. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Leroy Wayne Keiser, M.D. accept Medicare?
Leroy Wayne Keiser, M.D. appears in CMS Medicare data with 1,344 Part D claims and 328 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Leroy Wayne Keiser, M.D.'s credentials?
Leroy Wayne Keiser, M.D.'s NPI is 1417047283 with credentials M.D.. 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.