2026 NPPES data Optometrist NPI 1598755886 O.D.
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ROGER VESPER, O.D.

Optometrist in MARICOPA, Arizona. 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
118
Medicare Part D claims · 33 beneficiaries · Optometrist avg: 257
Generic prescribing
68%
generic claims · 32% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

ROGER VESPER, O.D. filed 118 Medicare Part D claims in 2023 as a Optometrist in MARICOPA, Arizona, prescribing 68% generic.

118
Part D claims, 2023
68%
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.

ROGER VESPER, O.D.'s Medicare Part D volume vs every U.S. prescriber

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

118 35th percentile higher than 35% 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

What does the federal data show about ROGER VESPER, O.D.?

Quality data not reported

NPI registry status

Active

Issued 10/26/2005

NPI 1598755886

Primary specialty

Optometrist

High-volume

60,463 US NPIs in this specialty

Medicare Part D claims

118 54% vs specialty avg

2023 prescription claims

Specialty avg: 257

Specialty distribution in Arizona

How Optometrist compares to other specialties among Arizona providers

Arizona providers

Optometrist share within Arizona

1. Optometrist42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Optometrist share within Arizona

Specialty board-certification context

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

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

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

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

ROGER VESPER, O.D. appears in the CMS NPPES registry as a Optometrist provider holding O.D. credentials at 21300 NORTH JOHN WAYNE PARKWAY, MARICOPA, AZ, 85239, with a listed phone of (520) 568-7538. NPI 1598755886 was issued on 10/26/2005. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what VESPER 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 118 prescription claims written by this provider, covering 33 Medicare beneficiaries and totaling roughly $4K in drug spend, split 32% brand-name and 68% 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.

Optometrist is a high-volume specialty nationwide, with 60,463 enrolled providers across 56 states and an average of 257 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

21300 NORTH JOHN WAYNE PARKWAY
MARICOPA, AZ 85239

Provider Details

NPI 1598755886
Specialty Optometrist
Credentials O.D.
Gender Male
NPI Issued 10/26/2005

Brand vs generic prescribing mix · Above average

ROGER VESPER, O.D. — brand share 32.0%
Specialty average (est.)

32% brand-name claims vs 68% generic, on 118 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.

118
Total Claims
$4K
Total Drug Cost
33
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
221
Total Day Supply
6,216
Brand vs Generic
32% brand / 68% generic
Brand Drug Cost
$3K
Generic Drug Cost
$2K

Patient Demographics

Average Patient Age
75.2 years
Avg HCC Risk Score
1.42
Gender Split
58% female / 42% male

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Latanoprost
63
Timolol Maleate
30

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

Optometrist Overview

How ROGER VESPER, O.D. fits within the Optometrist landscape nationally.

60,463
Optometrist Providers in US
56
States with Optometrist
257
Avg Claims per Provider

ROGER VESPER, O.D.'s 118 claims are below the specialty average of 257.

Nearby Optometrist Providers in Arizona

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

Compare Optometrist nationally: see state-by-state distribution →

Frequently Asked Questions

What is ROGER VESPER, O.D.'s specialty?
ROGER VESPER, O.D. specializes in Optometrist and practices in MARICOPA, Arizona. Credentials: O.D..
How much does ROGER VESPER, O.D. prescribe under Medicare Part D?
In 2023, ROGER VESPER, O.D. wrote 118 Medicare Part D claims totaling $4K in drug costs for 33 beneficiaries.
Where is ROGER VESPER, O.D. located?
ROGER VESPER, O.D. is located at 21300 NORTH JOHN WAYNE PARKWAY, MARICOPA, AZ, 85239. Phone: (520) 568-7538.
What is ROGER VESPER, O.D.'s NPI number?
ROGER VESPER, O.D.'s National Provider Identifier (NPI) is 1598755886, issued on 10/26/2005.
Does ROGER VESPER, O.D. prescribe more brand-name or generic drugs?
ROGER VESPER, O.D.'s prescribing is 32% brand-name and 68% generic drugs by claim count, with $3K in brand drug costs.
How many Optometrist providers are there in the US?
There are 60,463 Optometrist providers across 56 states in the US. The average Optometrist provider writes 257 Medicare Part D claims per year.
What drugs does ROGER VESPER, O.D. prescribe most often?
Based on 2023 Medicare Part D data, ROGER VESPER, O.D.'s most frequently prescribed drugs include Latanoprost, Timolol Maleate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does ROGER VESPER, O.D. accept Medicare?
ROGER VESPER, O.D. appears in CMS Medicare data with 118 Part D claims and 33 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify ROGER VESPER, O.D.'s credentials?
ROGER VESPER, O.D.'s NPI is 1598755886 with credentials O.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

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