NPI registry status
Active
2026 NPPES data Optometrist NPI 1528141348 O.D.
Verify on CMS → Gregory Farrell, O.D.
Optometrist in Princeton, Maine.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 61,426 in Optometrist, 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
199
Medicare Part D claims · 46 beneficiaries · Optometrist avg: 279
Generic prescribing
59%
generic claims · 41% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2024
What the federal data shows
Gregory Farrell, O.D. filed 199 Medicare Part D claims in 2024 as an Optometrist in Princeton, Maine, prescribing 59% generic.
- 199
- Part D claims, 2024
- 59%
- generic prescribing
- ≥34th
- pct by Part D claim volume (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 Gregory Farrell, O.D.
Federal records show an active NPI with Medicare Part D prescribing activity — verifiable registry data, not a proprietary rating.
- Verified
NPI registry status
Active listing in the CMS National Provider Identifier Registry (NPI 1528141348), first enumerated 10/23/2006.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 199 Medicare Part D prescription claims in the 2023 CMS public use file — indicates active Medicare prescribing participation.
Source: CMS Part D Prescriber PUF
- Reported
Hospital affiliations
1 CMS Care Compare hospital affiliation on record — practice footprint from the Doctors and Clinicians file.
Source: CMS Care Compare
- 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 1528141348 · Optometrist
NPI-10 · ENUM-LEGACY · TAX-MEGA · RX-LIGHT · BOOK-THIN · PHOTO-ENUM
- NPI-10 1528141348
- ENUM-LEGACY 2006
- TAX-MEGA 61K Optometrist
- RX-LIGHT 199
- BOOK-THIN 301 in Maine
- PHOTO-ENUM Vasvi Babu · 2006
Gregory Farrell, O.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
199 ≥ 34th percentile 34% of 1,416,883 prescribers are in lower value bands
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.
The percentile is a conservative 100-claim band: it counts only prescribers in lower claim-volume bands. Medicare Part D claim volume is activity context, not a quality measure or recommendation. See methodology § corpus placement.
Source CMS Medicare Part D Prescriber Public Use File · 2024
What does the federal data show about Gregory Farrell, O.D.?
Quality data not reportedPrimary specialty
Optometrist
Medicare Part D claims
199 29% vs specialty avg
Specialty distribution in Maine
How Optometrist compares to other specialties among Maine providers
Board certification
Not published by CMS
CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Optometrist. Verify directly:
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
Provider Details
| NPI | 1528141348 |
|---|---|
| Specialty | Optometrist |
| Credentials | O.D. |
| Gender | Male |
| NPI Issued | 10/23/2006 |
Hospital and facility affiliations
Facilities where Gregory Farrell, O.D. 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.
St Croix Regional Family Health Center
Princeton, ME
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 · Above average
Gregory Farrell, O.D. - brand share 41.0%
Optometrist average
41% brand-name claims vs 59% generic, on 199 2024 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 2024.
199
Total Claims
$26K
Total Drug Cost
46
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 268.5
- Total Day Supply
- 7,206
- Brand vs Generic
- 41% brand / 59% generic
- Brand Drug Cost
- $21K
- Generic Drug Cost
- $5K
Patient Demographics
- Average Patient Age
- 75.5 years
- Avg HCC Risk Score
- 1.21
- Gender Split
- 52% female / 48% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2024. Based on Medicare Part D data only.
What Gregory Farrell, O.D. prescribes most
Top Medicare Part D drugs by claim count, 2024
- Latanoprost
Latanoprost
69 claims
- Lumigan
Lumigan
51 claims
- Timolol Maleate 17
Timolol Maleate
17 claims
- Tobramycin-Dexamet… 13
Tobramycin-Dexamethasone
13 claims
- Brimonidine Tartrate 11
Brimonidine Tartrate
11 claims
| Drug | Claims |
|---|---|
| Latanoprost | 69 |
| Lumigan Bimatoprost | 51 |
| Timolol Maleate | 17 |
| Tobramycin-Dexamethasone Tobramycin/Dexamethasone | 13 |
| Brimonidine Tartrate | 11 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Optometrist Overview
How Gregory Farrell, O.D. fits within the Optometrist landscape nationally.
61,426
Optometrist Providers in US
56
States with Optometrist
279
Avg Claims per Provider
Gregory Farrell, O.D.'s 199 claims are below the specialty average of 279.
Nationwide Optometrist peers with similar MIPS or enrollment year
Two federal-record peer sets for Farrell, both outside Maine so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2006)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Optometrist Providers in Maine
Other clinicians with the same primary specialty enrolled in Maine, drawn from the same CMS NPPES roster as Farrell.
One of 301 Optometrist providers enrolled in Maine, 5 are shown here.
Dr. Amy Abbott
O.D.
South Portland, ME
Dr. Andre Achenbach
O.D.
Brunswick, ME
Dr. Rachel Achenbach
OD
Windham, ME
Dr. Nirupama Aggarwal
OD
Portland, ME
Dr. Paul Albert
O.D.
Ellsworth, ME
Compare Optometrist nationally: see state-by-state distribution →
Frequently Asked Questions
What is Gregory Farrell, O.D.'s specialty? ▼
Gregory Farrell, O.D. specializes in Optometrist and practices in Princeton, Maine. Credentials: O.D..
How much does Gregory Farrell, O.D. prescribe under Medicare Part D? ▼
In 2024, Gregory Farrell, O.D. wrote 199 Medicare Part D claims totaling $26K in drug costs for 46 beneficiaries.
Where is Gregory Farrell, O.D. located? ▼
Gregory Farrell, O.D. is located at 136 MILL ST, Princeton, ME, 04668. Phone: (207) 796-5033.
What is Gregory Farrell, O.D.'s NPI number? ▼
Gregory Farrell, O.D.'s National Provider Identifier (NPI) is 1528141348, issued on 10/23/2006.
Does Gregory Farrell, O.D. prescribe more brand-name or generic drugs? ▼
Gregory Farrell, O.D.'s prescribing is 41% brand-name and 59% generic drugs by claim count, with $21K in brand drug costs.
How many Optometrist providers are there in the US? ▼
There are 61,426 Optometrist providers across 56 states in the US. The average Optometrist provider writes 279 Medicare Part D claims per year.
What drugs does Gregory Farrell, O.D. prescribe most often? ▼
Based on 2024 Medicare Part D data, Gregory Farrell, O.D.'s most frequently prescribed drugs include Latanoprost, Lumigan, Timolol Maleate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Gregory Farrell, O.D. accept Medicare? ▼
Gregory Farrell, O.D. appears in CMS Medicare data with 199 Part D claims and 46 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Gregory Farrell, O.D.'s credentials? ▼
Gregory Farrell, O.D.'s NPI is 1528141348 with credentials O.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 (2024). 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 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
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.