NPI registry status
Active
2026 NPPES data Nephrology Physician NPI 1730180878 MD
Verify on CMS → John Maynard, MD
Nephrology Physician in Rockford, Illinois.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 10,569 in Nephrology 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 · 256 beneficiaries · Nephrology Physician avg: 1K
Generic prescribing
94%
generic claims · 6% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2023
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
John Maynard, MD filed 1,199 Medicare Part D claims in 2023 as a Nephrology Physician in Rockford, Illinois, prescribing 94% generic.
- 1K
- Part D claims, 2023
- 94%
- 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.
John Maynard, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
1,199 Top 23% higher than 77% of 1,370,886 prescribers
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)
John Maynard, 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 John Maynard, MD?
Quality data not reportedPrimary specialty
Nephrology Physician
Medicare Part D claims
1,199 18% vs specialty avg
Specialty distribution in Illinois
How Nephrology Physician compares to other specialties among Illinois 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 Nephrology 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).
John Maynard, MD appears in the CMS NPPES registry as a Nephrology Physician provider holding MD credentials at 612 ROXBURY RD, Rockford, IL, 61107, with a listed phone of (815) 227-8300. NPI 1730180878 was issued on 08/10/2005.
Medicare Part D records for calendar year 2023 show 1,199 prescription claims written by this provider, covering 256 Medicare beneficiaries and totaling roughly $86K in drug spend, split 6% brand-name and 94% generic by claim count.
Nephrology Physician is a mid-sized specialty nationwide, with 10,569 enrolled providers across 55 states and an average of 1,454 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
Provider Details
| NPI | 1730180878 |
|---|---|
| Specialty | Nephrology Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 08/10/2005 |
Hospital and facility affiliations
Facilities where John Maynard, 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.
Rna OF Rockford, PLLC
Rockford, IL
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
License & disciplinary context - Illinois IDFPR 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 ~42K Illinois medical licensees in 2023 - they are NOT specific to John Maynard, MD. To verify John Maynard, MD's current license status, search the IDFPR public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
106
Total board actions, Illinois 2023
Across 103 cases
2.52
Actions per 1,000 licensees
Illinois statewide rate
probation
Most common action type
38 cases
IDFPR 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 Illinois disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Brand vs generic prescribing mix · Generic-heavy
John Maynard, MD - brand share 6.0%
Nephrology Physician average
6% brand-name claims vs 94% generic, on 1,199 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.
1,199
Total Claims
$86K
Total Drug Cost
256
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 3,055
- Total Day Supply
- 90,528
- Brand vs Generic
- 6% brand / 94% generic
- Brand Drug Cost
- $41K
- Generic Drug Cost
- $45K
- Antibiotic Claims
- 18
Patient Demographics
- Average Patient Age
- 71.4 years
- Avg HCC Risk Score
- 3.79
- Gender Split
- 52% female / 48% male
- Age Distribution
- <65: 54, 65-74: 85, 75-84: 91, 85+: 26
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What John Maynard, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Lisinopril
Lisinopril
146 claims
- Terazosin Hcl
Terazosin Hcl
139 claims
- Calcitriol
Calcitriol
130 claims
- Furosemide
Furosemide
125 claims
- Losartan Potassium
Losartan Potassium
87 claims
- Vitamin D2
Vitamin D2
60 claims
- Metoprolol Succinate
Metoprolol Succinate
59 claims
- Atenolol 57
Atenolol
57 claims
| Drug | Claims |
|---|---|
| Lisinopril | 146 |
| Terazosin Hcl | 139 |
| Calcitriol | 130 |
| Furosemide | 125 |
| Losartan Potassium | 87 |
| Vitamin D2 Ergocalciferol (Vitamin D2) | 60 |
| Metoprolol Succinate | 59 |
| Atenolol | 57 |
| Sevelamer Carbonate | 44 |
| Farxiga Dapagliflozin Propanediol | 42 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Nephrology Physician Overview
How John Maynard, MD fits within the Nephrology Physician landscape nationally.
10,569
Nephrology Physician Providers in US
55
States with Nephrology Physician
1,454
Avg Claims per Provider
John Maynard, MD's 1,199 claims are below the specialty average of 1,454.
Nearby Nephrology Physician Providers in Illinois
Other clinicians with the same primary specialty enrolled in Illinois, drawn from the same CMS NPPES roster as Maynard.
Dr. Momen Abbasi
M.D.
Chicago, IL
Dr. Pabitra Adhikari
MD
Chicago, IL
Dr. Bhavani Adusumilli
MD
Springfield, IL
Dr. Muhammad Sohaib Afzal
MD, MBBS
Maywood, IL
Dr. Nidhi Aggarwal
M.D.
Chicago, IL
Compare Nephrology 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 Illinois medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Nephrology 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.
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Frequently Asked Questions
What is John Maynard, MD's specialty? ▼
John Maynard, MD specializes in Nephrology Physician and practices in Rockford, Illinois. Credentials: MD.
How much does John Maynard, MD prescribe under Medicare Part D? ▼
In 2023, John Maynard, MD wrote 1,199 Medicare Part D claims totaling $86K in drug costs for 256 beneficiaries.
Where is John Maynard, MD located? ▼
John Maynard, MD is located at 612 ROXBURY RD, Rockford, IL, 61107. Phone: (815) 227-8300.
What is John Maynard, MD's NPI number? ▼
John Maynard, MD's National Provider Identifier (NPI) is 1730180878, issued on 08/10/2005.
Does John Maynard, MD prescribe more brand-name or generic drugs? ▼
John Maynard, MD's prescribing is 6% brand-name and 94% generic drugs by claim count, with $41K in brand drug costs.
How many Nephrology Physician providers are there in the US? ▼
There are 10,569 Nephrology Physician providers across 55 states in the US. The average Nephrology Physician provider writes 1,454 Medicare Part D claims per year.
What drugs does John Maynard, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, John Maynard, MD's most frequently prescribed drugs include Lisinopril, Terazosin Hcl, Calcitriol. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does John Maynard, MD accept Medicare? ▼
John Maynard, MD appears in CMS Medicare data with 1,199 Part D claims and 256 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify John Maynard, MD's credentials? ▼
John Maynard, MD's NPI is 1730180878 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
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.