2026 NPPES data Specialist NPI 1073589396 M.D.
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CARLA WILLIAMS, M.D.

Specialist in GREENWICH, 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
241
Medicare Part D claims · 69 beneficiaries · Specialist avg: 1K
Generic prescribing
70%
generic claims · 30% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

CARLA WILLIAMS, M.D. filed 241 Medicare Part D claims in 2023 as a Specialist in GREENWICH, Connecticut, prescribing 70% generic.

241
Part D claims, 2023
70%
generic prescribing

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.

CARLA WILLIAMS, M.D.'s Medicare Part D volume vs every U.S. prescriber

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

241 49th percentile higher than 49% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). This entry sits in this band. 400–600: 90,619 prescribers (7%). Above this entry. 600–800: 56,224 prescribers (4%). Above this entry. 800–1,000: 40,919 prescribers (3%). Above this entry. 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

What does the federal data show about CARLA WILLIAMS, M.D.?

Quality data not reported

NPI registry status

Active

Issued 02/27/2006

NPI 1073589396

Primary specialty

Specialist

High-volume

69,658 US NPIs in this specialty

Medicare Part D claims

241 84% vs specialty avg

2023 prescription claims

Specialty avg: 1,474

Specialty distribution in Connecticut

How Specialist compares to other specialties among Connecticut providers

Connecticut providers

Specialist share within Connecticut

1. Specialist42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Specialist share within Connecticut

Specialty board-certification context

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

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

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

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

CARLA WILLIAMS, M.D. is a Specialist provider practicing in GREENWICH, Connecticut, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: M.D.. NPI: 1073589396. 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.

CARLA WILLIAMS, M.D. appears in the CMS NPPES registry as a Specialist provider holding M.D. credentials at 159 W PUTNAM AVE, GREENWICH, CT, 06830, with a listed phone of (203) 869-7080. NPI 1073589396 was issued on 02/27/2006. 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 241 prescription claims written by this provider, covering 69 Medicare beneficiaries and totaling roughly $42K in drug spend, split 30% brand-name and 70% 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.

Specialist is a high-volume specialty nationwide, with 69,658 enrolled providers across 55 states and an average of 1,474 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

159 W PUTNAM AVE
GREENWICH, CT 06830

Provider Details

NPI 1073589396
Specialty Specialist
Credentials M.D.
Gender Female
NPI Issued 02/27/2006

Brand vs generic prescribing mix · Above average

CARLA WILLIAMS, M.D. — brand share 30.0%
Specialty average (est.)

30% brand-name claims vs 70% generic, on 241 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.

241
Total Claims
$42K
Total Drug Cost
69
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
524
Total Day Supply
14,808
Brand vs Generic
30% brand / 70% generic
Brand Drug Cost
$25K
Generic Drug Cost
$17K

Patient Demographics

Average Patient Age
73.4 years
Avg HCC Risk Score
0.73
Gender Split
100% female / 0% male

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Estradiol
50
Yuvafem
Estradiol
20
Valacyclovir
Valacyclovir Hcl
16
Estring
Estradiol
14
Estradiol (Once Weekly)
Estradiol
11
Premarin
"Estrogens
N/A
Progesterone
"Progesterone
N/A

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

Specialist Overview

How CARLA WILLIAMS, M.D. fits within the Specialist landscape nationally.

69,658
Specialist Providers in US
55
States with Specialist
1,474
Avg Claims per Provider

CARLA WILLIAMS, M.D.'s 241 claims are below the specialty average of 1,474.

Nearby Specialist Providers in Connecticut

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

Compare Specialist nationally: see state-by-state distribution →

Frequently Asked Questions

What is CARLA WILLIAMS, M.D.'s specialty?
CARLA WILLIAMS, M.D. specializes in Specialist and practices in GREENWICH, Connecticut. Credentials: M.D..
How much does CARLA WILLIAMS, M.D. prescribe under Medicare Part D?
In 2023, CARLA WILLIAMS, M.D. wrote 241 Medicare Part D claims totaling $42K in drug costs for 69 beneficiaries.
Where is CARLA WILLIAMS, M.D. located?
CARLA WILLIAMS, M.D. is located at 159 W PUTNAM AVE, GREENWICH, CT, 06830. Phone: (203) 869-7080.
What is CARLA WILLIAMS, M.D.'s NPI number?
CARLA WILLIAMS, M.D.'s National Provider Identifier (NPI) is 1073589396, issued on 02/27/2006.
Does CARLA WILLIAMS, M.D. prescribe more brand-name or generic drugs?
CARLA WILLIAMS, M.D.'s prescribing is 30% brand-name and 70% generic drugs by claim count, with $25K in brand drug costs.
How many Specialist providers are there in the US?
There are 69,658 Specialist providers across 55 states in the US. The average Specialist provider writes 1,474 Medicare Part D claims per year.
What drugs does CARLA WILLIAMS, M.D. prescribe most often?
Based on 2023 Medicare Part D data, CARLA WILLIAMS, M.D.'s most frequently prescribed drugs include Estradiol, Yuvafem, Valacyclovir. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does CARLA WILLIAMS, M.D. accept Medicare?
CARLA WILLIAMS, M.D. appears in CMS Medicare data with 241 Part D claims and 69 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify CARLA WILLIAMS, M.D.'s credentials?
CARLA WILLIAMS, M.D.'s NPI is 1073589396 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.
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