2026 NPPES data Urology Physician NPI 1942436886 MD
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CHARLES CHANG, MD

Urology Physician in CONCORD, California. 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
957
Medicare Part D claims · 285 beneficiaries · Urology Physician avg: 1K

What the federal data shows

CHARLES CHANG, MD filed 957 Medicare Part D claims in 2023 as a Urology Physician in CONCORD, California.

957
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.

CHARLES CHANG, MD's Medicare Part D volume vs every U.S. prescriber

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

957 Top 25% higher than 75% 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%). This entry sits in this band. 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

Board certification likely (heuristic — not verified)

CHARLES CHANG, 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 CHARLES CHANG, MD?

Quality data not reported

NPI registry status

Active

Issued 06/05/2009

NPI 1942436886

Primary specialty

Urology Physician

Mid-sized

13,350 US NPIs in this specialty

Medicare Part D claims

957 25% vs specialty avg

2023 prescription claims

Specialty avg: 1,280

Specialty distribution in California

How Urology Physician compares to other specialties among California providers

California providers

Urology Physician share within California

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

Specialty board-certification context

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

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

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

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

CHARLES CHANG, MD appears in the CMS NPPES registry as a Urology Physician provider holding MD credentials at 2222 EAST ST STE 250, CONCORD, CA, 94520, with a listed phone of (925) 609-7220. NPI 1942436886 was issued on 06/05/2009. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what CHANG 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 957 prescription claims written by this provider, covering 285 Medicare beneficiaries and totaling roughly $162K 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.

Urology Physician is a mid-sized specialty nationwide, with 13,350 enrolled providers across 54 states and an average of 1,280 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

2222 EAST ST STE 250
CONCORD, CA 94520

Provider Details

NPI 1942436886
Specialty Urology Physician
Credentials MD
Gender Male
NPI Issued 06/05/2009

Hospital and facility affiliations

Facilities where CHARLES CHANG, 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.

JOHN MUIR PHYSICIAN NETWORK
CONCORD, CA

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 — California MBC 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 ~150K California medical licensees in 2023 — they are NOT specific to CHARLES CHANG, MD. To verify CHARLES CHANG, MD's current license status, search the MBC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

576
Total board actions, California 2023
Across 556 cases
3.84
Actions per 1,000 licensees
California statewide rate
probation
Most common action type
186 cases

MBC 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 California disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Medicare Part D Prescribing Data

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

957
Total Claims
$162K
Total Drug Cost
285
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
1,444
Total Day Supply
40,423
Generic Drug Cost
$16K
Antibiotic Claims
94

Patient Demographics

Average Patient Age
70.6 years
Avg HCC Risk Score
1.40
Gender Split
21% female / 79% male

Top Prescribed Drugs (Medicare Part D)

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

What CHARLES CHANG, 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
Tamsulosin Hcl
403
Myrbetriq
Mirabegron
87
Oxybutynin Chloride Er
Oxybutynin Chloride
78
Alfuzosin Hcl Er
Alfuzosin Hcl
65
Finasteride
58
Oxybutynin Chloride
46
Ciprofloxacin Hcl
38
Solifenacin Succinate
31
Nitrofurantoin Mono-Macro
Nitrofurantoin Monohyd/M-Cryst
18
Lupron Depot
Leuprolide Acetate
15

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

Urology Physician Overview

How CHARLES CHANG, MD fits within the Urology Physician landscape nationally.

13,350
Urology Physician Providers in US
54
States with Urology Physician
1,280
Avg Claims per Provider

CHARLES CHANG, MD's 957 claims are below the specialty average of 1,280.

Nearby Urology Physician Providers in California

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

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

Frequently Asked Questions

What is CHARLES CHANG, MD's specialty?
CHARLES CHANG, MD specializes in Urology Physician and practices in CONCORD, California. Credentials: MD.
How much does CHARLES CHANG, MD prescribe under Medicare Part D?
In 2023, CHARLES CHANG, MD wrote 957 Medicare Part D claims totaling $162K in drug costs for 285 beneficiaries.
Where is CHARLES CHANG, MD located?
CHARLES CHANG, MD is located at 2222 EAST ST STE 250, CONCORD, CA, 94520. Phone: (925) 609-7220.
What is CHARLES CHANG, MD's NPI number?
CHARLES CHANG, MD's National Provider Identifier (NPI) is 1942436886, issued on 06/05/2009.
How many Urology Physician providers are there in the US?
There are 13,350 Urology Physician providers across 54 states in the US. The average Urology Physician provider writes 1,280 Medicare Part D claims per year.
What drugs does CHARLES CHANG, MD prescribe most often?
Based on 2023 Medicare Part D data, CHARLES CHANG, MD's most frequently prescribed drugs include Tamsulosin Hcl, Myrbetriq, Oxybutynin Chloride Er. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does CHARLES CHANG, MD accept Medicare?
CHARLES CHANG, MD appears in CMS Medicare data with 957 Part D claims and 285 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify CHARLES CHANG, MD's credentials?
CHARLES CHANG, MD's NPI is 1942436886 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