2026 NPPES data Hematology & Oncology Physician NPI 1003850645 MD
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ZAHID DAR, MD

Hematology & Oncology Physician in OSHKOSH, Wisconsin. 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
1K
Medicare Part D claims · 312 beneficiaries · Hematology & Oncology Physician avg: 847
Generic prescribing
83%
generic claims · 17% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$48.78
1 payments · CMS Open Payments (Sunshine Act)

What the federal data shows

ZAHID DAR, MD filed 1,455 Medicare Part D claims in 2023 as a Hematology & Oncology Physician in OSHKOSH, Wisconsin, prescribing 83% generic.

1K
Part D claims, 2023
83%
generic prescribing
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.

ZAHID DAR, MD's Medicare Part D volume vs every U.S. prescriber

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

1,455 Top 20% higher than 80% 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%). Below this entry. 1,400–1,600: 21,710 prescribers (2%). This entry sits in this band. 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 certification likely (heuristic — not verified)

ZAHID DAR, MD 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 ZAHID DAR, MD?

Quality data not reported

NPI registry status

Active

Issued 06/15/2006

NPI 1003850645

Primary specialty

Hematology & Oncology Physician

Mid-sized

11,215 US NPIs in this specialty

Medicare Part D claims

1,455 72% vs specialty avg

2023 prescription claims

Specialty avg: 847

Specialty distribution in Wisconsin

How Hematology & Oncology Physician compares to other specialties among Wisconsin providers

Wisconsin providers

Hematology & Oncology Physician share within Wisconsin

1. Hematology & Oncology Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Hematology & Oncology Physician share within Wisconsin

Specialty board-certification context

Estimated specialty board-certified rate — Hematology & Oncology Physician (ABMS / AOA reference)

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

Est. board-certified rate (Hematology & Oncology Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Hematology & Oncology 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).

ZAHID DAR, MD appears in the CMS NPPES registry as a Hematology & Oncology Physician provider holding MD credentials at 855 N WESTHAVEN DR, OSHKOSH, WI, 54904, with a listed phone of (920) 303-8700. NPI 1003850645 was issued on 06/15/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what DAR 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 1,455 prescription claims written by this provider, covering 312 Medicare beneficiaries and totaling roughly $1.9 million in drug spend, split 17% brand-name and 83% generic by claim count, with an opioid prescribing rate of 2.3%. 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.

Hematology & Oncology Physician is a mid-sized specialty nationwide, with 11,215 enrolled providers across 54 states and an average of 847 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

855 N WESTHAVEN DR
OSHKOSH, WI 54904

Provider Details

NPI 1003850645
Specialty Hematology & Oncology Physician
Credentials MD
Gender Male
NPI Issued 06/15/2006

Hospital and facility affiliations

Facilities where ZAHID DAR, 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.

AURORA MEDICAL GROUP, INC.
MILWAUKEE, WI

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 ZAHID DAR, MD. Source: openpaymentsdata.cms.gov.

Total received

$49

Largest payer

Merck Sharp & Dohme LLC

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.

Brand vs generic prescribing mix · Typical

ZAHID DAR, MD — brand share 17.0%
Specialty average (est.)

17% brand-name claims vs 83% generic, on 1,455 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.

1,455
Total Claims
$1.9M
Total Drug Cost
312
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
2,314
Total Day Supply
63,046
Brand vs Generic
17% brand / 83% generic
Brand Drug Cost
$1.7M
Generic Drug Cost
$271K
Opioid Claims
33 (2.3% rate)
Antibiotic Claims
65

Patient Demographics

Average Patient Age
72.8 years
Avg HCC Risk Score
2.34
Gender Split
65% female / 35% male
Age Distribution
<65: 28, 65-74: 168, 75-84: 84, 85+: 32

Top Prescribed Drugs (Medicare Part D)

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

What ZAHID DAR, MD 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
Prochlorperazine Maleate
105
Acyclovir
95
Letrozole
95
Abiraterone Acetate
93
Prednisone
85
Anastrozole
74
Eliquis
Apixaban
56
Hydroxyurea
55
Alendronate Sodium
54
Dexamethasone
49

* 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 ZAHID DAR, MD fits within the Hematology & Oncology Physician landscape nationally.

11,215
Hematology & Oncology Physician Providers in US
54
States with Hematology & Oncology Physician
847
Avg Claims per Provider

ZAHID DAR, MD's 1,455 claims are above the specialty average of 847.

Nearby Hematology & Oncology Physician Providers in Wisconsin

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

Compare Hematology & Oncology Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is ZAHID DAR, MD's specialty?
ZAHID DAR, MD specializes in Hematology & Oncology Physician and practices in OSHKOSH, Wisconsin. Credentials: MD.
How much does ZAHID DAR, MD prescribe under Medicare Part D?
In 2023, ZAHID DAR, MD wrote 1,455 Medicare Part D claims totaling $1.9M in drug costs for 312 beneficiaries.
Where is ZAHID DAR, MD located?
ZAHID DAR, MD is located at 855 N WESTHAVEN DR, OSHKOSH, WI, 54904. Phone: (920) 303-8700.
What is ZAHID DAR, MD's NPI number?
ZAHID DAR, MD's National Provider Identifier (NPI) is 1003850645, issued on 06/15/2006.
Does ZAHID DAR, MD prescribe more brand-name or generic drugs?
ZAHID DAR, MD's prescribing is 17% brand-name and 83% generic drugs by claim count, with $1.7M in brand drug costs.
Does ZAHID DAR, MD prescribe opioids?
Yes, ZAHID DAR, MD had 33 opioid claims in 2023 with an opioid prescribing rate of 2.3%.
How many Hematology & Oncology Physician providers are there in the US?
There are 11,215 Hematology & Oncology Physician providers across 54 states in the US. The average Hematology & Oncology Physician provider writes 847 Medicare Part D claims per year.
What drugs does ZAHID DAR, MD prescribe most often?
Based on 2023 Medicare Part D data, ZAHID DAR, MD's most frequently prescribed drugs include Prochlorperazine Maleate, Acyclovir, Letrozole. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does ZAHID DAR, MD accept Medicare?
ZAHID DAR, MD appears in CMS Medicare data with 1,455 Part D claims and 312 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify ZAHID DAR, MD's credentials?
ZAHID DAR, MD's NPI is 1003850645 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