2026 NPPES data Hospitalist Physician NPI 1366707580 MD
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JOHN WILLIAMS, MD

Hospitalist Physician in MIDDLETOWN, Connecticut. 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 · 210 beneficiaries · Hospitalist Physician avg: 888
Generic prescribing
91%
generic claims · 9% brand-name · higher generic rates reduce patient out-of-pocket costs
MIPS score
97.2738/100
▲ 14 pts above national avg 83.1 · [object Object]

What the federal data shows

JOHN WILLIAMS, MD reported a CMS MIPS final score of 97.2738/100 — above the 83.1 national average — and filed 1,919 Medicare Part D claims in 2023.

97.2738/100
MIPS score · +14 vs avg
2K
Part D claims, 2023
91%
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 WILLIAMS, MD's MIPS score vs every scored U.S. clinician

CMS Merit-based Incentive Payment System (MIPS) final score, 2023 — the federal quality measure

97 Top 15% higher than 85% of 477,587 scored providers

0–10: 8,684 scored providers (2%). Below this entry. 10–20: 3,008 scored providers (1%). Below this entry. 20–30: 3,069 scored providers (1%). Below this entry. 30–40: 2,746 scored providers (1%). Below this entry. 40–50: 2,928 scored providers (1%). Below this entry. 50–60: 5,882 scored providers (1%). Below this entry. 60–70: 13,906 scored providers (3%). Below this entry. 70–80: 118,074 scored providers (25%). Below this entry. 80–90: 129,887 scored providers (27%). Below this entry. 90–100: 189,403 scored providers (40%). This entry sits in this band. This provider 0 100 every MIPS-scored clinician, bucketed by value

Each bar is a band; taller bars hold more scored 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.

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

Board certification likely (heuristic — not verified)

JOHN WILLIAMS, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + MIPS quality reporting + 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 WILLIAMS, MD?

High performer (top quartile)

NPI registry status

Active

Issued 07/13/2012

NPI 1366707580

Primary specialty

Hospitalist Physician

Mid-sized

16,825 US NPIs in this specialty

Medicare Part D claims

1,919 116% vs specialty avg

2023 prescription claims

Specialty avg: 888

MIPS final score

97.2738/100 14.1738% pts

Exceptional band

vs 83.1 national avg

Specialty distribution in Connecticut

How Hospitalist Physician compares to other specialties among Connecticut providers

Connecticut providers

Hospitalist Physician share within Connecticut

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

Medicare quality performance — MIPS

JOHN WILLIAMS, MD's 2023 MIPS final score plotted against the Hospitalist Physician national average

High performer (top quartile)
MIPS Final Score
97.2738/100
vs 83.1 national avg · 2023 performance year

MIPS final score (Hospitalist Physician) — 97.2738/100 vs national avg 83.1

0%100%National avg83%97.3%
MIPS final score (Hospitalist Physician) — 97.2738/100 vs national avg 83.1

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 WILLIAMS, MD appears in the CMS NPPES registry as a Hospitalist Physician provider holding MD credentials at 90 S MAIN ST, MIDDLETOWN, CT, 06457, with a listed phone of (860) 358-6486. NPI 1366707580 was issued on 07/13/2012. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what WILLIAMS 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 1,919 prescription claims written by this provider, covering 210 Medicare beneficiaries and totaling roughly $162K in drug spend, split 9% brand-name and 91% generic by claim count, with an opioid prescribing rate of 0.8%. 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. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 97.2738/100 for the 2023 performance year (Quality 81.6843), compared with the national average of 83.1.

Hospitalist Physician is a mid-sized specialty nationwide, with 16,825 enrolled providers across 54 states and an average of 888 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

90 S MAIN ST
MIDDLETOWN, CT 06457

Provider Details

NPI 1366707580
Specialty Hospitalist Physician
Credentials MD
Gender Male
NPI Issued 07/13/2012

CMS Quality Score (MIPS)

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

97.2738
Final Score
Avg: 83.1
81.6843
Quality
100
Promoting Interoperability

Reporting: Alternative Payment Model

Hospital and facility affiliations

Facilities where JOHN WILLIAMS, 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.

MIDDLESEX HOSPITAL
★★★☆☆ 3/5
MIDDLETOWN, CT
Acute Care Hospitals
CMS CCN: 070020

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

Brand vs generic prescribing mix · Generic-heavy

JOHN WILLIAMS, MD — brand share 9.0%
Specialty average (est.)

9% brand-name claims vs 91% generic, on 1,919 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.

1,919
Total Claims
$162K
Total Drug Cost
210
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
4,256
Total Day Supply
125,169
Brand vs Generic
9% brand / 91% generic
Brand Drug Cost
$123K
Generic Drug Cost
$38K
Opioid Claims
16 (0.8% rate)

Patient Demographics

Average Patient Age
75.3 years
Avg HCC Risk Score
1.33
Gender Split
48% female / 52% male
Age Distribution
<65: 17, 65-74: 84, 75-84: 73, 85+: 36

Top Prescribed Drugs (Medicare Part D)

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

What JOHN WILLIAMS, 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
Atorvastatin Calcium
174
Amlodipine Besylate
131
Lisinopril
89
Levothyroxine Sodium
73
Hydrochlorothiazide
66
Sertraline Hcl
51
Pravastatin Sodium
45
Zolpidem Tartrate
45
Metformin Hcl
44
Losartan Potassium
43

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

Hospitalist Physician Overview

How JOHN WILLIAMS, MD fits within the Hospitalist Physician landscape nationally.

16,825
Hospitalist Physician Providers in US
54
States with Hospitalist Physician
888
Avg Claims per Provider

JOHN WILLIAMS, MD's 1,919 claims are above the specialty average of 888.

Nearby Hospitalist Physician Providers in Connecticut

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

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

Frequently Asked Questions

What is JOHN WILLIAMS, MD's specialty?
JOHN WILLIAMS, MD specializes in Hospitalist Physician and practices in MIDDLETOWN, Connecticut. Credentials: MD.
How much does JOHN WILLIAMS, MD prescribe under Medicare Part D?
In 2023, JOHN WILLIAMS, MD wrote 1,919 Medicare Part D claims totaling $162K in drug costs for 210 beneficiaries.
What is JOHN WILLIAMS, MD's Medicare quality score?
JOHN WILLIAMS, MD has a CMS MIPS Final Score of 97.2738/100 (Quality: 81.6843). The national average MIPS Final Score is 83.1. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is JOHN WILLIAMS, MD located?
JOHN WILLIAMS, MD is located at 90 S MAIN ST, MIDDLETOWN, CT, 06457. Phone: (860) 358-6486.
What is JOHN WILLIAMS, MD's NPI number?
JOHN WILLIAMS, MD's National Provider Identifier (NPI) is 1366707580, issued on 07/13/2012.
Does JOHN WILLIAMS, MD prescribe more brand-name or generic drugs?
JOHN WILLIAMS, MD's prescribing is 9% brand-name and 91% generic drugs by claim count, with $123K in brand drug costs.
Does JOHN WILLIAMS, MD prescribe opioids?
Yes, JOHN WILLIAMS, MD had 16 opioid claims in 2023 with an opioid prescribing rate of 0.8%.
How many Hospitalist Physician providers are there in the US?
There are 16,825 Hospitalist Physician providers across 54 states in the US. The average Hospitalist Physician provider writes 888 Medicare Part D claims per year.
What drugs does JOHN WILLIAMS, MD prescribe most often?
Based on 2023 Medicare Part D data, JOHN WILLIAMS, MD's most frequently prescribed drugs include Atorvastatin Calcium, Amlodipine Besylate, Lisinopril. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does JOHN WILLIAMS, MD accept Medicare?
JOHN WILLIAMS, MD appears in CMS Medicare data with 1,919 Part D claims and 210 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify JOHN WILLIAMS, MD's credentials?
JOHN WILLIAMS, MD's NPI is 1366707580 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.
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 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