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2026 NPPES data Endocrinology, Diabetes & Metabolism Physician NPI 1942304977 M.D., PHD
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Jeffrey Williams, M.D., PHD

Endocrinology, Diabetes & Metabolism Physician in Santa Cruz, California.

This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 8,078 in Endocrinology, Diabetes & Metabolism 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.
MIPS score
34.6/100
▼ 49 pts below national avg 83.5 · Below average
Verify NPI on CMS Methodology
Compiled from official public sources by the editorial process.

What the federal data shows

Jeffrey Williams, M.D., PHD reported a CMS MIPS final score of 34.6/100 - below the 83.5 national average.

34.6/100
MIPS score · -49 vs avg
Likely
board-certified (heuristic)
≥4th
pct among measured MIPS (lower-bound band)

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.

Federal trust snapshot

What official records show about Jeffrey Williams, M.D., PHD

Federal records show an active NPI with a CMS quality score on file — objective federal reporting, not patient reviews.

  • Verified

    NPI registry status

    Active listing in the CMS National Provider Identifier Registry (NPI 1942304977), first enumerated 09/11/2006.

    Source: CMS NPPES

  • Not in federal data

    Medicare Part D participation

    No 2023 Medicare Part D prescribing volume appears in the CMS public file for this NPI (may reflect specialty, new enrollment, or non-prescribing role).

    Source: CMS Part D Prescriber PUF

  • Reported

    CMS quality reporting (MIPS)

    Reported a CMS MIPS final score of 34.6/100 in the Quality Payment Program — a federal quality measure, not a patient review.

    Source: CMS Quality Payment Program

  • Reported

    Board certification signal

    Heuristic suggests board-certified status based on ABMS-eligible specialty taxonomy plus active CMS participation signals — not a direct ABMS verification.

    Source: NUCC taxonomy + CMS participation heuristic

  • State context

    State board disciplinary context

    California statewide board action statistics are published annually — these figures describe aggregate state activity, not Jeffrey Williams, M.D., PHD's individual license status. Verify directly with the state medical board.

    Source: MBC annual report 2023

  • Not in federal data

    Individual sanction lookup

    PlainDoctor does not publish per-provider disciplinary determinations. Confirm current license and any individual actions through the state medical board or FSMB verification service.

    Source: State medical board / FSMB

This trust snapshot summarizes only what appears in federal CMS/NPPES public records. It is not a composite score, star rating, patient review, or clinical recommendation. PlainDoctor never fabricates reviews or AggregateRating schema.

CMS NPPES provider registry desk

NPI 1942304977 · Endocrinology, Diabetes & Metabolism Physician

NPI-10 · ENUM-LEGACY · TAX-MID · MIPS-LOW · BOOK-LIGHT · PHOTO-FINISH

  • NPI-10 1942304977
  • ENUM-LEGACY 2006
  • TAX-MID 8K Endocrinology, Diabetes
  • MIPS-LOW 34.6/100
  • BOOK-LIGHT 890 in California
  • PHOTO-FINISH John Reynolds · ±0.3

MIPS final-score neighbourhood

Same-specialty nationwide peers by CMS final score, not geographic proximity

MIPS pts

What this shows Nearest measured MIPS peers for this NUCC specialty (2023 performance year).

Source CMS Quality Payment Program (MIPS) As of 2023

Jeffrey Williams, M.D., PHD's MIPS score vs every measured U.S. clinician

CMS Merit-based Incentive Payment System (MIPS) final score, 2023, the federal quality measure. Clinicians whose score CMS assigned without scoring any category are excluded.

35 ≥ 4th percentile 4% of 454,083 measured providers are in lower value bands

0–10: 8,684 measured providers (2%). Below this entry. 10–20: 3,008 measured providers (1%). Below this entry. 20–30: 3,069 measured providers (1%). Below this entry. 30–40: 2,746 measured providers (1%). This entry sits in this band. 40–50: 2,928 measured providers (1%). Above this entry. 50–60: 5,882 measured providers (1%). Above this entry. 60–70: 13,906 measured providers (3%). Above this entry. 70–80: 94,570 measured providers (21%). Above this entry. 80–90: 129,887 measured providers (29%). Above this entry. 90+: 189,403 measured providers (42%). Above this entry. This provider 0 100 every measured MIPS clinician, bucketed by value

Each bar is a band; taller bars hold more measured providers. 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.

The percentile is a conservative whole-score-point band: it counts only measured clinicians in lower score bands. A CMS MIPS metric is not a recommendation or a clinical-quality rating by PlainDoctor. See methodology § corpus placement.

Source CMS Merit-based Incentive Payment System (MIPS) · 2023

✓
Board certification likely (heuristic, not verified)

Jeffrey Williams, M.D., PHD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + MIPS quality reporting - 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 Jeffrey Williams, M.D., PHD?

Below national average

NPI registry status

Active

Issued 09/11/2006

NPI 1942304977

Primary specialty

Endocrinology, Diabetes & Metabolism Physician

Mid-sized

8,078 US NPIs in this specialty

MIPS final score

34.6/100 48.9 pts vs avg

Below average band

vs 83.5 national avg

Specialty distribution in California

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

California providers
Behavior Technician17.9%Marriage & Family Therapist5.4%Student in an Organized Heal…5.1%Mental Health Counselor3.7%Pharmacist3.4%Clinical Social Worker3.1%Endocrinology, Diabetes & Me…0.1%
Largest specialties in California (% of in-state providers)

Medicare quality performance, MIPS

Jeffrey Williams, M.D., PHD's 2023 MIPS final score plotted against the Endocrinology, Diabetes & Metabolism Physician national average

Below national average
MIPS Final Score
34.6/100
vs 83.5 national avg · 2023 performance year
0%100%National avg84%34.6%
MIPS final score (Endocrinology, Diabetes & Metabolism Physician) - 34.6/100 vs national avg 83.5
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).

Practice Address

1595 SOQUEL DR
Santa Cruz, CA 95065
(831) 465-7778

Provider Details

NPI 1942304977
Specialty Endocrinology, Diabetes & Metabolism Physician
Credentials M.D., PHD
Gender Male
NPI Issued 09/11/2006

CMS Quality Score (MIPS)

Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.

34.5839
Final Score
Measured-score avg: 83.5
15.4303
Quality
63.0993
Cost
0
Promoting Interoperability

Reporting: Group practice

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 Jeffrey Williams, M.D., PHD. To verify Jeffrey Williams, M.D., PHD'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.

More Endocrinology, Diabetes & Metabolism Physician in CA → All providers in California → Compare specialties →

Endocrinology, Diabetes & Metabolism Physician Overview

How Jeffrey Williams, M.D., PHD fits within the Endocrinology, Diabetes & Metabolism Physician landscape nationally.

8,078
Endocrinology, Diabetes & Metabolism Physician Providers in US
54
States with Endocrinology, Diabetes & Metabolism Physician
2,739
Avg Claims per Provider

Nationwide Endocrinology, Diabetes & Metabolism Physician peers with similar MIPS or enrollment year

Two federal-record peer sets for Williams, both outside California so the neighborhoods are not geographic containment.

Similar MIPS final score

Nearest same-specialty clinicians by CMS MIPS final score (34.6 here).

John Reynolds 34.9 NM Henry Bone 34.3 MI Hershel Jackson 33.7 MI Thomas Jones 33 GA

Same NPPES enumeration year (2006)

Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.

Elena Barengolts Arlington Heights, IL Stephen Quevedo New London, CT Robert Rizza Rochester, MN Mary Baker Oklahoma City, OK

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 Williams.

One of 890 Endocrinology, Diabetes & Metabolism Physician providers enrolled in California, 5 are shown here.

Dr. Anita Abraham
M.D.
Stockton, CA
Dr. Sallie Adams
M.D.
Roseville, CA
Ananta Addala
Palo Alto, CA
Dr. Helen Adelberg
M.D.
Encino, CA
Dr. David Aftergood
MD
Beverly Hills, CA

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

Frequently Asked Questions

What is Jeffrey Williams, M.D., PHD's specialty? ▼
Jeffrey Williams, M.D., PHD specializes in Endocrinology, Diabetes & Metabolism Physician and practices in Santa Cruz, California. Credentials: M.D., PHD.
What is Jeffrey Williams, M.D., PHD's Medicare quality score? ▼
Jeffrey Williams, M.D., PHD has a CMS MIPS Final Score of 34.6/100 (Quality: 15.4, Cost: 63.1). The average MIPS Final Score across the 454,083 clinicians with at least one published category score is 83.5; clinicians whose score CMS assigned without scoring any category are excluded from that average. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is Jeffrey Williams, M.D., PHD located? ▼
Jeffrey Williams, M.D., PHD is located at 1595 SOQUEL DR, Santa Cruz, CA, 95065. Phone: (831) 465-7778.
What is Jeffrey Williams, M.D., PHD's NPI number? ▼
Jeffrey Williams, M.D., PHD's National Provider Identifier (NPI) is 1942304977, issued on 09/11/2006.
How many Endocrinology, Diabetes & Metabolism Physician providers are there in the US? ▼
There are 8,078 Endocrinology, Diabetes & Metabolism Physician providers across 54 states in the US. The average Endocrinology, Diabetes & Metabolism Physician provider writes 2,739 Medicare Part D claims per year.
Does Jeffrey Williams, M.D., PHD accept Medicare? ▼
Jeffrey Williams, M.D., PHD appears in CMS Medicare data. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Jeffrey Williams, M.D., PHD's credentials? ▼
Jeffrey Williams, M.D., PHD's NPI is 1942304977 with credentials M.D., PHD. 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.
Quality Performance
CMS Merit-based Incentive Payment System (MIPS) - 2023 performance year.
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 August 2026 (NPPES) / 2024 (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 editorial process.

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 August 2026.