2026 NPPES data Endocrinology, Diabetes & Metabolism Physician NPI 1548204506 MD
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GEORGE CHAO, MD

Endocrinology, Diabetes & Metabolism Physician in MODESTO, 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
18K
Medicare Part D claims · 1K beneficiaries · Endocrinology, Diabetes & Metabolism Physician avg: 3K
Generic prescribing
63%
generic claims · 37% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$2.8K
33 payments · CMS Open Payments (Sunshine Act)

What the federal data shows

GEORGE CHAO, MD filed 17,729 Medicare Part D claims in 2023 as a Endocrinology, Diabetes & Metabolism Physician in MODESTO, California, prescribing 63% generic.

18K
Part D claims, 2023
63%
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.

GEORGE CHAO, MD's Medicare Part D volume vs every U.S. prescriber

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

17,729 Top 2% higher than 98% 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%). Below this entry. 1,800–2,000: 16,451 prescribers (1%). Below this entry. 2,000–2,200: 213,991 prescribers (16%). This entry sits in this band. 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)

GEORGE CHAO, 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 GEORGE CHAO, MD?

Quality data not reported

NPI registry status

Active

Issued 06/16/2006

NPI 1548204506

Primary specialty

Endocrinology, Diabetes & Metabolism Physician

Mid-sized

7,852 US NPIs in this specialty

Medicare Part D claims

17,729 572% vs specialty avg

2023 prescription claims

Specialty avg: 2,639

Specialty distribution in California

How Endocrinology, Diabetes & Metabolism Physician compares to other specialties among California providers

California providers

Endocrinology, Diabetes & Metabolism Physician share within California

1. Endocrinology, Diabetes & Metabolism Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Endocrinology, Diabetes & Metabolism Physician share within California

Specialty board-certification context

Estimated specialty board-certified rate — Endocrinology, Diabetes & Metabolism Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Endocrinology, Diabetes & Metabolism Physician ABMS/AOA estimate

Est. board-certified rate (Endocrinology, Diabetes & Metabolism Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Endocrinology, Diabetes & Metabolism 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).

GEORGE CHAO, MD is a Endocrinology, Diabetes & Metabolism Physician provider practicing in MODESTO, California, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: MD. NPI: 1548204506. This profile includes practice location, specialty classification, and organizational affiliations from the CMS provider registry. Provider information is self-reported to CMS and updated monthly.

GEORGE CHAO, MD appears in the CMS NPPES registry as a Endocrinology, Diabetes & Metabolism Physician provider holding MD credentials at 600 COFFEE RD, MODESTO, CA, 95355, with a listed phone of (209) 524-1211. NPI 1548204506 was issued on 06/16/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what CHAO 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 17,729 prescription claims written by this provider, covering 1,388 Medicare beneficiaries and totaling roughly $7.5 million in drug spend, split 37% brand-name and 63% 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.

Endocrinology, Diabetes & Metabolism Physician is a mid-sized specialty nationwide, with 7,852 enrolled providers across 54 states and an average of 2,639 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

600 COFFEE RD
MODESTO, CA 95355

Provider Details

NPI 1548204506
Specialty Endocrinology, Diabetes & Metabolism Physician
Credentials MD
Gender Male
NPI Issued 06/16/2006

Hospital and facility affiliations

Facilities where GEORGE CHAO, 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.

SUTTER VALLEY MEDICAL FOUNDATION
SACRAMENTO, 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).

Industry payments received (2024) — CMS Open Payments transparency data

The federal Physician Payments Sunshine Act (part of the Affordable Care Act) requires drug and medical-device manufacturers + group purchasing organizations to publicly report payments and other transfers of value to physicians and teaching hospitals. The data below covers 2024 for GEORGE CHAO, MD. Source: openpaymentsdata.cms.gov.

Total received

$2.8K

Largest payer

BETA BIONICS, INC.

Most common payment type

Food and Beverage

Industry payments are not necessarily indicators of bias — they include research funding, consulting fees for evidence-based work, royalties for inventions, food at conferences, and similar items. The disclosure exists for transparency. Read our methodology for how we interpret this data.

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 GEORGE CHAO, MD. To verify GEORGE CHAO, 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.

Brand vs generic prescribing mix · Above average

GEORGE CHAO, MD — brand share 37.0%
Specialty average (est.)

37% brand-name claims vs 63% generic, on 17,729 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.

17,729
Total Claims
$7.5M
Total Drug Cost
1,388
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
43,092
Total Day Supply
1,283,171
Brand vs Generic
37% brand / 63% generic
Brand Drug Cost
$7.0M
Generic Drug Cost
$399K
Antibiotic Claims
18

Patient Demographics

Average Patient Age
74.2 years
Avg HCC Risk Score
1.57
Gender Split
58% female / 42% male
Age Distribution
<65: 119, 65-74: 566, 75-84: 549, 85+: 154

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Atorvastatin Calcium
1,724
Levothyroxine Sodium
1,356
Ezetimibe
1,192
Pioglitazone Hcl
1,016
Jardiance
Empagliflozin
789
Farxiga
Dapagliflozin Propanediol
626
Metformin Hcl Er
Metformin Hcl
617
Metformin Hcl
614
Glipizide Er
Glipizide
598
Ozempic
Semaglutide
534

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

Endocrinology, Diabetes & Metabolism Physician Overview

How GEORGE CHAO, MD fits within the Endocrinology, Diabetes & Metabolism Physician landscape nationally.

7,852
Endocrinology, Diabetes & Metabolism Physician Providers in US
54
States with Endocrinology, Diabetes & Metabolism Physician
2,639
Avg Claims per Provider

GEORGE CHAO, MD's 17,729 claims are above the specialty average of 2,639.

Nearby Endocrinology, Diabetes & Metabolism Physician Providers in California

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

Compare Endocrinology, Diabetes & Metabolism Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is GEORGE CHAO, MD's specialty?
GEORGE CHAO, MD specializes in Endocrinology, Diabetes & Metabolism Physician and practices in MODESTO, California. Credentials: MD.
How much does GEORGE CHAO, MD prescribe under Medicare Part D?
In 2023, GEORGE CHAO, MD wrote 17,729 Medicare Part D claims totaling $7.5M in drug costs for 1,388 beneficiaries.
Where is GEORGE CHAO, MD located?
GEORGE CHAO, MD is located at 600 COFFEE RD, MODESTO, CA, 95355. Phone: (209) 524-1211.
What is GEORGE CHAO, MD's NPI number?
GEORGE CHAO, MD's National Provider Identifier (NPI) is 1548204506, issued on 06/16/2006.
Does GEORGE CHAO, MD prescribe more brand-name or generic drugs?
GEORGE CHAO, MD's prescribing is 37% brand-name and 63% generic drugs by claim count, with $7.0M in brand drug costs.
How many Endocrinology, Diabetes & Metabolism Physician providers are there in the US?
There are 7,852 Endocrinology, Diabetes & Metabolism Physician providers across 54 states in the US. The average Endocrinology, Diabetes & Metabolism Physician provider writes 2,639 Medicare Part D claims per year.
What drugs does GEORGE CHAO, MD prescribe most often?
Based on 2023 Medicare Part D data, GEORGE CHAO, MD's most frequently prescribed drugs include Atorvastatin Calcium, Levothyroxine Sodium, Ezetimibe. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does GEORGE CHAO, MD accept Medicare?
GEORGE CHAO, MD appears in CMS Medicare data with 17,729 Part D claims and 1,388 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify GEORGE CHAO, MD's credentials?
GEORGE CHAO, MD's NPI is 1548204506 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