2026 NPPES data Hospitalist Physician NPI 1033402862 M.D.
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WILLIAM GRAY, M.D.

Hospitalist Physician in DERBY, 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
13
Medicare Part D claims · 11 beneficiaries · Hospitalist Physician avg: 888
MIPS score
75/100
▼ 8 pts below national avg 83.1 · [object Object]
Industry payments
$575.41
15 payments · CMS Open Payments (Sunshine Act)
What the federal data reveals: WILLIAM GRAY, M.D. is a Hospitalist Physician ([object Object]) practicing in DERBY, Connecticut with a Medicare Part D prescribing footprint of 13 claims across 11 beneficiaries . Their CMS MIPS Final Score of 75/100 (national average: 83.1) reflects performance across Quality, Cost, Interoperability, and Improvement Activities . Industry payments of $575.41 across 15 transactions are disclosed under CMS Open Payments (Sunshine Act).

What stands out: WILLIAM GRAY, M.D. reported a CMS MIPS final score of 75 out of 100, below the 83.1 national average, and filed 13 Medicare Part D claims in 2023. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

WILLIAM GRAY, M.D. 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).

WILLIAM GRAY, M.D. at a glance

Below national average

NPI registry status

Active

Issued 05/26/2011

NPI 1033402862

Primary specialty

Hospitalist Physician

Mid-sized

16,825 US NPIs in this specialty

Medicare Part D claims

13 99% vs specialty avg

2023 prescription claims

Specialty avg: 888

MIPS final score

75/100 8.099999999999994% pts

Above neutral 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

WILLIAM GRAY, M.D.'s 2023 MIPS final score plotted against the Hospitalist Physician national average

Below national average
MIPS Final Score
75/100
vs 83.1 national avg · 2023 performance year

MIPS final score (Hospitalist Physician) — 75/100 vs national avg 83.1

0%100%National avg83%75%
MIPS final score (Hospitalist Physician) — 75/100 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).

WILLIAM GRAY, M.D. is a Hospitalist Physician provider practicing in DERBY, Connecticut, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: M.D.. NPI: 1033402862. 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.

WILLIAM GRAY, M.D. appears in the CMS NPPES registry as a Hospitalist Physician provider holding M.D. credentials at 130 DIVISION ST, DERBY, CT, 06418, with a listed phone of (203) 732-1330. NPI 1033402862 was issued on 05/26/2011. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what GRAY 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 13 prescription claims written by this provider, covering 11 Medicare beneficiaries and totaling roughly $340 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. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 75/100 for the 2023 performance year, 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

130 DIVISION ST
DERBY, CT 06418

Provider Details

NPI 1033402862
Specialty Hospitalist Physician
Credentials M.D.
Gender Male
NPI Issued 05/26/2011

CMS Quality Score (MIPS)

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

75
Final Score
Avg: 83.1

Reporting: Group practice

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 WILLIAM GRAY, M.D.. Source: openpaymentsdata.cms.gov.

Total received

$575

Largest payer

Organogenesis 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.

Medicare Part D Prescribing Data

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

13
Total Claims
$340
Total Drug Cost
11
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
13
Total Day Supply
169

Patient Demographics

Average Patient Age
81.3 years
Avg HCC Risk Score
2.69
Age Distribution
<65: 0, 65-74: N/A, 75-84: N/A, 85+: N/A

Hospitalist Physician Overview

How WILLIAM GRAY, M.D. fits within the Hospitalist Physician landscape nationally.

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

WILLIAM GRAY, M.D.'s 13 claims are below 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 GRAY.

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

Frequently Asked Questions

What is WILLIAM GRAY, M.D.'s specialty?
WILLIAM GRAY, M.D. specializes in Hospitalist Physician and practices in DERBY, Connecticut. Credentials: M.D..
How much does WILLIAM GRAY, M.D. prescribe under Medicare Part D?
In 2023, WILLIAM GRAY, M.D. wrote 13 Medicare Part D claims totaling $340 in drug costs for 11 beneficiaries.
What is WILLIAM GRAY, M.D.'s Medicare quality score?
WILLIAM GRAY, M.D. has a CMS MIPS Final Score of 75/100. The national average MIPS Final Score is 83.1. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is WILLIAM GRAY, M.D. located?
WILLIAM GRAY, M.D. is located at 130 DIVISION ST, DERBY, CT, 06418. Phone: (203) 732-1330.
What is WILLIAM GRAY, M.D.'s NPI number?
WILLIAM GRAY, M.D.'s National Provider Identifier (NPI) is 1033402862, issued on 05/26/2011.
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.
Does WILLIAM GRAY, M.D. accept Medicare?
WILLIAM GRAY, M.D. appears in CMS Medicare data with 13 Part D claims and 11 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify WILLIAM GRAY, M.D.'s credentials?
WILLIAM GRAY, M.D.'s NPI is 1033402862 with credentials M.D.. 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