2026 NPPES data Nephrology Physician NPI 1104827427 MD
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JAMES STIM, MD

Nephrology Physician in ROCKFORD, Illinois. 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
2K
Medicare Part D claims · 366 beneficiaries · Nephrology Physician avg: 1K
Generic prescribing
94%
generic claims · 6% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

JAMES STIM, MD filed 1,781 Medicare Part D claims in 2023 as a Nephrology Physician in ROCKFORD, Illinois, prescribing 94% generic.

2K
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.

JAMES STIM, MD's Medicare Part D volume vs every U.S. prescriber

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

1,781 Top 17% higher than 83% 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%). Below this entry. 1,600–1,800: 19,072 prescribers (1%). This entry sits in this band. 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)

JAMES STIM, 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 JAMES STIM, MD?

Quality data not reported

NPI registry status

Active

Issued 08/09/2005

NPI 1104827427

Primary specialty

Nephrology Physician

Mid-sized

10,534 US NPIs in this specialty

Medicare Part D claims

1,781 22% vs specialty avg

2023 prescription claims

Specialty avg: 1,454

Specialty distribution in Illinois

How Nephrology Physician compares to other specialties among Illinois providers

Illinois providers

Nephrology Physician share within Illinois

1. Nephrology Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Nephrology Physician share within Illinois

Specialty board-certification context

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

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

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

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

JAMES STIM, 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 1104827427 was issued on 08/09/2005. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what STIM 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 1,781 prescription claims written by this provider, covering 366 Medicare beneficiaries and totaling roughly $115K in drug spend, split 6% brand-name and 94% 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.

Nephrology Physician is a mid-sized specialty nationwide, with 10,534 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

612 ROXBURY RD
ROCKFORD, IL 61107

Provider Details

NPI 1104827427
Specialty Nephrology Physician
Credentials MD
Gender Male
NPI Issued 08/09/2005

Hospital and facility affiliations

Facilities where JAMES STIM, 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
BELOIT, 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).

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 JAMES STIM, MD. To verify JAMES STIM, 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

JAMES STIM, MD — brand share 6.0%
Specialty average (est.)

6% brand-name claims vs 94% generic, on 1,781 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.

1,781
Total Claims
$115K
Total Drug Cost
366
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
4,128
Total Day Supply
121,653
Brand vs Generic
6% brand / 94% generic
Brand Drug Cost
$67K
Generic Drug Cost
$48K
Antibiotic Claims
47

Patient Demographics

Average Patient Age
72.3 years
Avg HCC Risk Score
3.96
Gender Split
53% female / 47% male
Age Distribution
<65: 70, 65-74: 121, 75-84: 123, 85+: 52

Top Prescribed Drugs (Medicare Part D)

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

What JAMES STIM, 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
Calcitriol
277
Amlodipine Besylate
186
Losartan Potassium
126
Torsemide
110
Furosemide
108
Lisinopril
92
Hydralazine Hcl
79
Potassium Chloride
65
Farxiga
Dapagliflozin Propanediol
55
Vitamin D2
Ergocalciferol (Vitamin D2)
51

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

Nephrology Physician Overview

How JAMES STIM, MD fits within the Nephrology Physician landscape nationally.

10,534
Nephrology Physician Providers in US
55
States with Nephrology Physician
1,454
Avg Claims per Provider

JAMES STIM, MD's 1,781 claims are above 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 STIM.

Compare Nephrology Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is JAMES STIM, MD's specialty?
JAMES STIM, MD specializes in Nephrology Physician and practices in ROCKFORD, Illinois. Credentials: MD.
How much does JAMES STIM, MD prescribe under Medicare Part D?
In 2023, JAMES STIM, MD wrote 1,781 Medicare Part D claims totaling $115K in drug costs for 366 beneficiaries.
Where is JAMES STIM, MD located?
JAMES STIM, MD is located at 612 ROXBURY RD, ROCKFORD, IL, 61107. Phone: (815) 227-8300.
What is JAMES STIM, MD's NPI number?
JAMES STIM, MD's National Provider Identifier (NPI) is 1104827427, issued on 08/09/2005.
Does JAMES STIM, MD prescribe more brand-name or generic drugs?
JAMES STIM, MD's prescribing is 6% brand-name and 94% generic drugs by claim count, with $67K in brand drug costs.
How many Nephrology Physician providers are there in the US?
There are 10,534 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 JAMES STIM, MD prescribe most often?
Based on 2023 Medicare Part D data, JAMES STIM, MD's most frequently prescribed drugs include Calcitriol, Amlodipine Besylate, Losartan Potassium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does JAMES STIM, MD accept Medicare?
JAMES STIM, MD appears in CMS Medicare data with 1,781 Part D claims and 366 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify JAMES STIM, MD's credentials?
JAMES STIM, MD's NPI is 1104827427 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