NPI registry status
Active
2026 NPPES data Urology Physician NPI 1770802357 M.D.
Verify on CMS → Catherine Alonzo, M.D.
Urology Physician in Greenwich, Connecticut.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 13,367 in Urology 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.
Prescribing volume
294
Medicare Part D claims · 139 beneficiaries · Urology Physician avg: 1K
Generic prescribing
73%
generic claims · 27% brand-name · higher generic rates reduce patient out-of-pocket costs
MIPS score
73.6/100
▼ 10 pts below national avg 83.1 · Mid-tier
Source: CMS Medicare Part D Prescriber Public Use File, 2023
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
Catherine Alonzo, M.D. reported a CMS MIPS final score of 73.6/100 - below the 83.1 national average - and filed 294 Medicare Part D claims in 2023.
- 73.6/100
- MIPS score · -10 vs avg
- 294
- Part D claims, 2023
- 73%
- 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.
Catherine Alonzo, M.D.'s MIPS score vs every scored U.S. clinician
CMS Merit-based Incentive Payment System (MIPS) final score, 2023, the federal quality measure
74 11th percentile higher than 11% of 477,587 scored providers
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
Where Catherine Alonzo, M.D. sits
This provider among urology physician peers
Across the 4,623 urology physician providers who report both Medicare Part D prescribing and a MIPS quality score, Catherine Alonzo, M.D. writes more Part D claims than 15% of them and scores higher on MIPS quality than 10% - placing this provider in the lower-volume, lower-quality quadrant. Volume reflects patient-panel size and specialty, not quality; the two axes are independent.
Part D claim volume vs MIPS quality, by specialty percentile
Each dot is one urology physician peer from a representative sample of 60; the gold marker is Catherine Alonzo, M.D.. Source: CMS Medicare Part D Prescriber data and the CMS Merit-based Incentive Payment System, 2023.
✓
Board certification likely (heuristic, not verified)
Catherine Alonzo, 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).
What does the federal data show about Catherine Alonzo, M.D.?
Below national averagePrimary specialty
Urology Physician
Medicare Part D claims
294 77% vs specialty avg
MIPS final score
73.6/100 9.5 pts vs avg
Specialty distribution in Connecticut
How Urology Physician compares to other specialties among Connecticut providers
Medicare quality performance, MIPS
Catherine Alonzo, M.D.'s 2023 MIPS final score plotted against the Urology Physician national average
- MIPS Final Score
- 73.6/100
- vs 83.1 national avg · 2023 performance year
MIPS final score (Urology Physician) - 73.6/100 vs national avg 83.1
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).
Catherine Alonzo, M.D. appears in the CMS NPPES registry as a Urology Physician provider holding M.D. credentials at 49 LAKE AVE, Greenwich, CT, 06830, with a listed phone of (203) 869-1285. NPI 1770802357 was issued on 05/22/2010.
Medicare Part D records for calendar year 2023 show 294 prescription claims written by this provider, covering 139 Medicare beneficiaries and totaling roughly $72K in drug spend, split 27% brand-name and 73% generic by claim count. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 73.6/100 for the 2023 performance year (Quality 75.8, Cost 51.4), compared with the national average of 83.1.
Urology Physician is a mid-sized specialty nationwide, with 13,367 enrolled providers across 54 states and an average of 1,280 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
Provider Details
| NPI | 1770802357 |
|---|---|
| Specialty | Urology Physician |
| Credentials | M.D. |
| Gender | Female |
| NPI Issued | 05/22/2010 |
CMS Quality Score (MIPS)
Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.
73.5637
Final Score
Avg: 83.1
75.8435
Quality
51.4318
Cost
74
Promoting Interoperability
Reporting: Group practice
Brand vs generic prescribing mix · Above average
Catherine Alonzo, M.D. - brand share 27.0%
Urology Physician average
27% brand-name claims vs 73% generic, on 294 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.
294
Total Claims
$72K
Total Drug Cost
139
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 743
- Total Day Supply
- 22,147
- Brand vs Generic
- 27% brand / 73% generic
- Brand Drug Cost
- $57K
- Generic Drug Cost
- $16K
Patient Demographics
- Average Patient Age
- 78.7 years
- Avg HCC Risk Score
- 1.17
- Gender Split
- 48% female / 52% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Catherine Alonzo, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2023
- Myrbetriq
Myrbetriq
69 claims
- Tamsulosin Hcl
Tamsulosin Hcl
57 claims
- Dutasteride
Dutasteride
30 claims
- Alfuzosin Hcl Er 22
Alfuzosin Hcl Er
22 claims
- Methenamine Hippur… 21
Methenamine Hippurate
21 claims
- Finasteride 19
Finasteride
19 claims
- Estradiol 17
Estradiol
17 claims
- Silodosin 15
Silodosin
15 claims
| Drug | Claims |
|---|---|
| Myrbetriq Mirabegron | 69 |
| Tamsulosin Hcl | 57 |
| Dutasteride | 30 |
| Alfuzosin Hcl Er Alfuzosin Hcl | 22 |
| Methenamine Hippurate | 21 |
| Finasteride | 19 |
| Estradiol | 17 |
| Silodosin | 15 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Urology Physician Overview
How Catherine Alonzo, M.D. fits within the Urology Physician landscape nationally.
13,367
Urology Physician Providers in US
54
States with Urology Physician
1,280
Avg Claims per Provider
Catherine Alonzo, M.D.'s 294 claims are below the specialty average of 1,280.
Nearby Urology Physician Providers in Connecticut
Other clinicians with the same primary specialty enrolled in Connecticut, drawn from the same CMS NPPES roster as Alonzo.
Dr. Syed Alam
MD
New Haven, CT
Dr. Peter Albertsen
M.D.
Farmington, CT
Dr. Rudy Andriani
MD
Stamford, CT
Dr. Joseph Antoci
M. D.
Middlebury, CT
Dr. Corlis Archer-Goode
M.D.
New Britain, CT
Compare Urology Physician nationally: see state-by-state distribution →
Before you book an appointment
Use this federal record as your verification checklist, not as a recommendation.
- Confirm the NPI record is current in the official CMS registry, providers update their own NPPES details, and moves can lag. Verify this NPI
- Check the active license and any disciplinary history with the Connecticut medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Urology Physician peer on Medicare volume and prescribing patterns. Compare providers
Medicare Part D and MIPS figures describe practice patterns in federal programs only, they are not quality ratings, and PlainDoctor does not rate, rank, or recommend providers.
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Frequently Asked Questions
What is Catherine Alonzo, M.D.'s specialty? ▼
Catherine Alonzo, M.D. specializes in Urology Physician and practices in Greenwich, Connecticut. Credentials: M.D..
How much does Catherine Alonzo, M.D. prescribe under Medicare Part D? ▼
In 2023, Catherine Alonzo, M.D. wrote 294 Medicare Part D claims totaling $72K in drug costs for 139 beneficiaries.
What is Catherine Alonzo, M.D.'s Medicare quality score? ▼
Catherine Alonzo, M.D. has a CMS MIPS Final Score of 73.6/100 (Quality: 75.8, Cost: 51.4). The national average MIPS Final Score is 83.1. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is Catherine Alonzo, M.D. located? ▼
Catherine Alonzo, M.D. is located at 49 LAKE AVE, Greenwich, CT, 06830. Phone: (203) 869-1285.
What is Catherine Alonzo, M.D.'s NPI number? ▼
Catherine Alonzo, M.D.'s National Provider Identifier (NPI) is 1770802357, issued on 05/22/2010.
Does Catherine Alonzo, M.D. prescribe more brand-name or generic drugs? ▼
Catherine Alonzo, M.D.'s prescribing is 27% brand-name and 73% generic drugs by claim count, with $57K in brand drug costs.
How many Urology Physician providers are there in the US? ▼
There are 13,367 Urology Physician providers across 54 states in the US. The average Urology Physician provider writes 1,280 Medicare Part D claims per year.
What drugs does Catherine Alonzo, M.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, Catherine Alonzo, M.D.'s most frequently prescribed drugs include Myrbetriq, Tamsulosin Hcl, Dutasteride. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Catherine Alonzo, M.D. accept Medicare? ▼
Catherine Alonzo, M.D. appears in CMS Medicare data with 294 Part D claims and 139 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Catherine Alonzo, M.D.'s credentials? ▼
Catherine Alonzo, M.D.'s NPI is 1770802357 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
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.
- 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
Compiled from official public sources by the PlainDoctor editorial team.
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 May 2026.