NPI registry status
Active
2026 NPPES data Optometrist NPI 1831181668 OD
Verify on CMS → John Ferrell, OD
Optometrist in Webster City, Iowa.
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
848
Medicare Part D claims · 163 beneficiaries · Optometrist avg: 279
Generic prescribing
77%
generic claims · 23% 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
John Ferrell, OD filed 848 Medicare Part D claims in 2024 as an Optometrist in Webster City, Iowa, prescribing 77% generic.
- 848
- Part D claims, 2024
- 77%
- generic prescribing
- ≥72nd
- 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 John Ferrell, OD
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 1831181668), first enumerated 08/18/2005.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 848 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 1831181668 · Optometrist
NPI-10 · ENUM-LEGACY · TAX-MEGA · RX-LIGHT · BOOK-LIGHT · PHOTO-ENUM
- NPI-10 1831181668
- ENUM-LEGACY 2005
- TAX-MEGA 61K Optometrist
- RX-LIGHT 848
- BOOK-LIGHT 667 in Iowa
- PHOTO-ENUM Philip Marler, OD · 2005
John Ferrell, OD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
848 ≥ 72nd percentile 72% 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 John Ferrell, OD?
Quality data not reportedPrimary specialty
Optometrist
Medicare Part D claims
848 204% vs specialty avg
Specialty distribution in Iowa
How Optometrist compares to other specialties among Iowa 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 | 1831181668 |
|---|---|
| Specialty | Optometrist |
| Credentials | OD |
| Gender | Male |
| NPI Issued | 08/18/2005 |
Hospital and facility affiliations
Facilities where John Ferrell, OD 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.
Mitchell County Memorial Hospital
Osage, IA
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 · Typical
John Ferrell, OD - brand share 23.0%
Optometrist average
23% brand-name claims vs 77% generic, on 848 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.
848
Total Claims
$58K
Total Drug Cost
163
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 1,230.733
- Total Day Supply
- 33,075
- Brand vs Generic
- 23% brand / 77% generic
- Brand Drug Cost
- $49K
- Generic Drug Cost
- $9K
- Antibiotic Claims
- 17
Patient Demographics
- Average Patient Age
- 77.6 years
- Avg HCC Risk Score
- 0.95
- Gender Split
- 58% female / 42% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2024. Based on Medicare Part D data only.
What John Ferrell, OD prescribes most
Top Medicare Part D drugs by claim count, 2024
- Latanoprost
Latanoprost
303 claims
- Dorzolamide-Timolol 108
Dorzolamide-Timolol
108 claims
- Lumigan 86
Lumigan
86 claims
- Timolol Maleate 63
Timolol Maleate
63 claims
- Combigan 54
Combigan
54 claims
- Moxifloxacin 52
Moxifloxacin
52 claims
- Brimonidine Tartrate 43
Brimonidine Tartrate
43 claims
- Dorzolamide Hcl 25
Dorzolamide Hcl
25 claims
| Drug | Claims |
|---|---|
| Latanoprost | 303 |
| Dorzolamide-Timolol Dorzolamide Hcl/Timolol Maleat | 108 |
| Lumigan Bimatoprost | 86 |
| Timolol Maleate | 63 |
| Combigan Brimonidine Tartrate/Timolol | 54 |
| Moxifloxacin Moxifloxacin Hcl | 52 |
| Brimonidine Tartrate | 43 |
| Dorzolamide Hcl | 25 |
| Brimonidine Tartrate-Timolol Brimonidine Tartrate/Timolol | 19 |
| Tobramycin-Dexamethasone Tobramycin/Dexamethasone | 18 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Optometrist Overview
How John Ferrell, OD fits within the Optometrist landscape nationally.
61,426
Optometrist Providers in US
56
States with Optometrist
279
Avg Claims per Provider
John Ferrell, OD's 848 claims are above the specialty average of 279.
Nationwide Optometrist peers with similar MIPS or enrollment year
Two federal-record peer sets for Ferrell, both outside Iowa so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2005)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Optometrist Providers in Iowa
Other clinicians with the same primary specialty enrolled in Iowa, drawn from the same CMS NPPES roster as Ferrell.
One of 667 Optometrist providers enrolled in Iowa, 5 are shown here.
Dr. Ryan Ackerman
O.D.
Rock Rapids, IA
Dr. Katie Adams
OD
West Union, IA
Dr. Paul Ahern
O.D.
Dyersville, IA
Dr. George Alberhasky
O.D., P.C.
Iowa City, IA
Dr. Troy Albrecht
OD
Marion, IA
Compare Optometrist nationally: see state-by-state distribution →
Frequently Asked Questions
What is John Ferrell, OD's specialty? ▼
John Ferrell, OD specializes in Optometrist and practices in Webster City, Iowa. Credentials: OD.
How much does John Ferrell, OD prescribe under Medicare Part D? ▼
In 2024, John Ferrell, OD wrote 848 Medicare Part D claims totaling $58K in drug costs for 163 beneficiaries.
Where is John Ferrell, OD located? ▼
John Ferrell, OD is located at 1620 SUPERIOR ST, Webster City, IA, 50595. Phone: (515) 832-2401.
What is John Ferrell, OD's NPI number? ▼
John Ferrell, OD's National Provider Identifier (NPI) is 1831181668, issued on 08/18/2005.
Does John Ferrell, OD prescribe more brand-name or generic drugs? ▼
John Ferrell, OD's prescribing is 23% brand-name and 77% generic drugs by claim count, with $49K 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 John Ferrell, OD prescribe most often? ▼
Based on 2024 Medicare Part D data, John Ferrell, OD's most frequently prescribed drugs include Latanoprost, Dorzolamide-Timolol, Lumigan. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does John Ferrell, OD accept Medicare? ▼
John Ferrell, OD appears in CMS Medicare data with 848 Part D claims and 163 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify John Ferrell, OD's credentials? ▼
John Ferrell, OD's NPI is 1831181668 with credentials OD. 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.