NPI registry status
Active
2026 NPPES data Hematology & Oncology Physician NPI 1063406163 M.D.
Verify on CMS → David Koster, M.D.
Hematology & Oncology Physician in Fresno, 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 11,530 in Hematology & Oncology 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
595
Medicare Part D claims · 170 beneficiaries · Hematology & Oncology Physician avg: 885
Generic prescribing
78%
generic claims · 22% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2024
What the federal data shows
David Koster, M.D. filed 595 Medicare Part D claims in 2024 as a Hematology & Oncology Physician in Fresno, California, prescribing 78% generic.
- 595
- Part D claims, 2024
- 78%
- generic prescribing
- ≥65th
- pct by Part D claim volume (lower-bound band)
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.
Federal trust snapshot
What official records show about David Koster, M.D.
Federal records show an active NPI with Medicare Part D prescribing activity — verifiable registry data, not a proprietary rating.
- Verified
NPI registry status
Active listing in the CMS National Provider Identifier Registry (NPI 1063406163), first enumerated 09/02/2005.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 595 Medicare Part D prescription claims in the 2023 CMS public use file — indicates active Medicare prescribing participation.
Source: CMS Part D Prescriber PUF
- Reported
Board certification signal
Practices in an ABMS-board-eligible specialty; board certification not confirmed in federal records.
- State context
State board disciplinary context
California statewide board action statistics are published annually — these figures describe aggregate state activity, not David Koster, M.D.'s individual license status. Verify directly with the state medical board.
Source: MBC annual report 2023
- Not in federal data
Individual sanction lookup
PlainDoctor does not publish per-provider disciplinary determinations. Confirm current license and any individual actions through the state medical board or FSMB verification service.
Source: State medical board / FSMB
This trust snapshot summarizes only what appears in federal CMS/NPPES public records. It is not a composite score, star rating, patient review, or clinical recommendation. PlainDoctor never fabricates reviews or AggregateRating schema.
CMS NPPES provider registry desk
NPI 1063406163 · Hematology & Oncology Physician
NPI-10 · ENUM-LEGACY · TAX-MID · RX-LIGHT · BOOK-LIGHT · PHOTO-ENUM
- NPI-10 1063406163
- ENUM-LEGACY 2005
- TAX-MID 12K Hematology &
- RX-LIGHT 595
- BOOK-LIGHT 1,306 in California
- PHOTO-ENUM David Henry · 2005
David Koster, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
595 ≥ 65th percentile 65% of 1,416,883 prescribers are in lower value bands
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.
The percentile is a conservative 100-claim band: it counts only prescribers in lower claim-volume bands. Medicare Part D claim volume is activity context, not a quality measure or recommendation. See methodology § corpus placement.
Source CMS Medicare Part D Prescriber Public Use File · 2024
◑
Board-eligible specialty (heuristic, not verified)
David Koster, M.D. 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 David Koster, M.D.?
Quality data not reportedPrimary specialty
Hematology & Oncology Physician
Medicare Part D claims
595 33% vs specialty avg
Specialty distribution in California
How Hematology & Oncology Physician compares to other specialties among California 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 & Oncology 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).
Practice Address
Provider Details
| NPI | 1063406163 |
|---|---|
| Specialty | Hematology & Oncology Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 09/02/2005 |
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 David Koster, M.D.. To verify David Koster, 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.
Brand vs generic prescribing mix · Typical
David Koster, M.D. - brand share 22.0%
Hematology & Oncology Physician average
22% brand-name claims vs 78% generic, on 595 2024 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 2024.
595
Total Claims
$2.1M
Total Drug Cost
170
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 811.9
- Total Day Supply
- 21,738
- Brand vs Generic
- 22% brand / 78% generic
- Brand Drug Cost
- $1.9M
- Generic Drug Cost
- $233K
- Opioid Claims
- 27 (4.5% rate)
- Antibiotic Claims
- 17
Patient Demographics
- Average Patient Age
- 71.9 years
- Avg HCC Risk Score
- 2.22
- Gender Split
- 54% female / 46% male
- Age Distribution
- <65: 22, 65-74: 87, 75-84: 46, 85+: 15
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2024. Based on Medicare Part D data only.
What David Koster, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2024
- Anastrozole
Anastrozole
51 claims
- Prochlorperazine M…
Prochlorperazine Maleate
43 claims
- Imbruvica
Imbruvica
36 claims
- Ondansetron Hcl
Ondansetron Hcl
28 claims
- Abiraterone Acetate
Abiraterone Acetate
27 claims
- Prednisone
Prednisone
27 claims
- Acyclovir
Acyclovir
25 claims
- Xtandi
Xtandi
23 claims
| Drug | Claims |
|---|---|
| Anastrozole | 51 |
| Prochlorperazine Maleate | 43 |
| Imbruvica Ibrutinib | 36 |
| Ondansetron Hcl | 28 |
| Abiraterone Acetate | 27 |
| Prednisone | 27 |
| Acyclovir | 25 |
| Xtandi Enzalutamide | 23 |
| Letrozole | 20 |
| Hydroxyurea | 17 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Hematology & Oncology Physician Overview
How David Koster, M.D. fits within the Hematology & Oncology Physician landscape nationally.
11,530
Hematology & Oncology Physician Providers in US
54
States with Hematology & Oncology Physician
885
Avg Claims per Provider
David Koster, M.D.'s 595 claims are below the specialty average of 885.
Nationwide Hematology & Oncology Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Koster, both outside California so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2005)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Hematology & Oncology Physician Providers in California
Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as Koster.
One of 1,306 Hematology & Oncology Physician providers enrolled in California, 5 are shown here.
Dr. Mark Abate
M.D.
Santa Barbara, CA
Dr. Iman Abdalla
MD
Los Angeles, CA
Dr. Nihal Abdulla
MD
Los Alamitos, CA
Dr. Oyewale Abidoye
M.D.
La Jolla, CA
Dr. Mohamad Adada
M.D., PHD
Roseville, CA
Compare Hematology & Oncology Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is David Koster, M.D.'s specialty? ▼
David Koster, M.D. specializes in Hematology & Oncology Physician and practices in Fresno, California. Credentials: M.D..
How much does David Koster, M.D. prescribe under Medicare Part D? ▼
In 2024, David Koster, M.D. wrote 595 Medicare Part D claims totaling $2.1M in drug costs for 170 beneficiaries.
Where is David Koster, M.D. located? ▼
David Koster, M.D. is located at 7130 N MILLBROOK AVE, Fresno, CA, 93720. Phone: (559) 326-1238.
What is David Koster, M.D.'s NPI number? ▼
David Koster, M.D.'s National Provider Identifier (NPI) is 1063406163, issued on 09/02/2005.
Does David Koster, M.D. prescribe more brand-name or generic drugs? ▼
David Koster, M.D.'s prescribing is 22% brand-name and 78% generic drugs by claim count, with $1.9M in brand drug costs.
Does David Koster, M.D. prescribe opioids? ▼
Yes, David Koster, M.D. had 27 opioid claims in 2024 with an opioid prescribing rate of 4.5%.
How many Hematology & Oncology Physician providers are there in the US? ▼
There are 11,530 Hematology & Oncology Physician providers across 54 states in the US. The average Hematology & Oncology Physician provider writes 885 Medicare Part D claims per year.
What drugs does David Koster, M.D. prescribe most often? ▼
Based on 2024 Medicare Part D data, David Koster, M.D.'s most frequently prescribed drugs include Anastrozole, Prochlorperazine Maleate, Imbruvica. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does David Koster, M.D. accept Medicare? ▼
David Koster, M.D. appears in CMS Medicare data with 595 Part D claims and 170 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify David Koster, M.D.'s credentials? ▼
David Koster, M.D.'s NPI is 1063406163 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 (2024). 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 August 2026 (NPPES) / 2024 (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
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 August 2026.