2026 NPPES data Rheumatology Physician NPI 1083696751 M.D.
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Lester Mertz, M.D.

Rheumatology Physician in Scottsdale, Arizona. This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 6,181 in Rheumatology 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
583
Medicare Part D claims · 163 beneficiaries · Rheumatology Physician avg: 2K
Compiled from official public sources by the PlainDoctor editorial team.

What the federal data shows

Lester Mertz, M.D. filed 583 Medicare Part D claims in 2023 as a Rheumatology Physician in Scottsdale, Arizona.

583
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.

Lester Mertz, M.D.'s Medicare Part D volume vs every U.S. prescriber

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

583 Top 34% higher than 66% 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%). This entry sits in this band. 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. 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)

Lester Mertz, 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 Lester Mertz, M.D.?

Quality data not reported

NPI registry status

Active

Issued 11/17/2005

NPI 1083696751

Primary specialty

Rheumatology Physician

Mid-sized

6,181 US NPIs in this specialty

Medicare Part D claims

583 72% vs specialty avg

2023 prescription claims

Specialty avg: 2,054

Specialty distribution in Arizona

How Rheumatology Physician compares to other specialties among Arizona providers

Arizona providers
Pharmacist - 5.6%Pharmacist5.6%Behavior Technician - 5.6%Behavior Technician5.6%Family Nurse Practitioner - 4.3%Family Nurse Practitioner4.3%Physical Therapist - 4.2%Physical Therapist4.2%Speech-Language Pathologist - 3.5%Speech-Language Pathologist3.5%Student in an Organized Health Care Education/Training Program - 3.5%Student in an Organized Health Care Education/Training Program3.5%Rheumatology Physician - 0.1%Rheumatology Physician0.1%
Largest specialties in Arizona (% 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 Rheumatology Physician. Verify directly:

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).

Lester Mertz, M.D. appears in the CMS NPPES registry as a Rheumatology Physician provider holding M.D. credentials at 13400 E SHEA BLVD, Scottsdale, AZ, 85259, with a listed phone of (480) 301-8000. NPI 1083696751 was issued on 11/17/2005. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what Mertz 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 583 prescription claims written by this provider, covering 163 Medicare beneficiaries and totaling roughly $536K in drug spend. 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.

Rheumatology Physician is a mid-sized specialty nationwide, with 6,181 enrolled providers across 52 states and an average of 2,054 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

13400 E SHEA BLVD
Scottsdale, AZ 85259

Provider Details

NPI 1083696751
Specialty Rheumatology Physician
Credentials M.D.
Gender Male
NPI Issued 11/17/2005

Hospital and facility affiliations

Facilities where Lester Mertz, 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.

Mayo Clinic Arizona
Scottsdale, AZ

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

Medicare Part D Prescribing Data

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

583
Total Claims
$536K
Total Drug Cost
163
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
1,370
Total Day Supply
40,486
Generic Drug Cost
$27K
Antibiotic Claims
28

Patient Demographics

Average Patient Age
74.1 years
Avg HCC Risk Score
1.88
Gender Split
60% female / 40% male

Top Prescribed Drugs (Medicare Part D)

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

What Lester Mertz, 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
Prednisone
162
Hydroxychloroquine Sulfate
38
Methotrexate
Methotrexate Sodium
38
Allopurinol
33
Azathioprine
31
Mycophenolate Mofetil
31
Sulfamethoxazole-Trimethoprim
Sulfamethoxazole/Trimethoprim
26
Colchicine
14
Rinvoq
Upadacitinib
14
Actemra
Tocilizumab
13

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

Rheumatology Physician Overview

How Lester Mertz, M.D. fits within the Rheumatology Physician landscape nationally.

6,181
Rheumatology Physician Providers in US
52
States with Rheumatology Physician
2,054
Avg Claims per Provider

Lester Mertz, M.D.'s 583 claims are below the specialty average of 2,054.

Nearby Rheumatology Physician Providers in Arizona

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

Compare Rheumatology 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 Arizona medical board, federal registration is not a license check. Credential verification guide
  • Weigh a second option: compare this provider with a nearby Rheumatology 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 Lester Mertz, M.D.'s specialty?
Lester Mertz, M.D. specializes in Rheumatology Physician and practices in Scottsdale, Arizona. Credentials: M.D..
How much does Lester Mertz, M.D. prescribe under Medicare Part D?
In 2023, Lester Mertz, M.D. wrote 583 Medicare Part D claims totaling $536K in drug costs for 163 beneficiaries.
Where is Lester Mertz, M.D. located?
Lester Mertz, M.D. is located at 13400 E SHEA BLVD, Scottsdale, AZ, 85259. Phone: (480) 301-8000.
What is Lester Mertz, M.D.'s NPI number?
Lester Mertz, M.D.'s National Provider Identifier (NPI) is 1083696751, issued on 11/17/2005.
How many Rheumatology Physician providers are there in the US?
There are 6,181 Rheumatology Physician providers across 52 states in the US. The average Rheumatology Physician provider writes 2,054 Medicare Part D claims per year.
What drugs does Lester Mertz, M.D. prescribe most often?
Based on 2023 Medicare Part D data, Lester Mertz, M.D.'s most frequently prescribed drugs include Prednisone, Hydroxychloroquine Sulfate, Methotrexate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Lester Mertz, M.D. accept Medicare?
Lester Mertz, M.D. appears in CMS Medicare data with 583 Part D claims and 163 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Lester Mertz, M.D.'s credentials?
Lester Mertz, M.D.'s NPI is 1083696751 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

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.