2026 NPPES data Ophthalmology Physician NPI 1952468274 M.D., FRCSC
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DELFRED DIEHL, M.D., FRCSC

Ophthalmology Physician in SEATTLE, Washington. 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
56
Medicare Part D claims · 33 beneficiaries · Ophthalmology Physician avg: 1K
What the federal data reveals: DELFRED DIEHL, M.D., FRCSC is a Ophthalmology Physician ([object Object]) practicing in SEATTLE, Washington with a Medicare Part D prescribing footprint of 56 claims across 33 beneficiaries .

What the federal data shows

DELFRED DIEHL, M.D., FRCSC filed 56 Medicare Part D claims in 2023 as a Ophthalmology Physician in SEATTLE, Washington.

56
Part D claims, 2023

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.

Board-eligible specialty (heuristic — not verified)

DELFRED DIEHL, M.D., FRCSC practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).

DELFRED DIEHL, M.D., FRCSC at a glance

Quality data not reported

NPI registry status

Active

Issued 01/03/2007

NPI 1952468274

Primary specialty

Ophthalmology Physician

Mid-sized

22,090 US NPIs in this specialty

Medicare Part D claims

56 96% vs specialty avg

2023 prescription claims

Specialty avg: 1,420

Specialty distribution in Washington

How Ophthalmology Physician compares to other specialties among Washington providers

Washington providers

Ophthalmology Physician share within Washington

1. Ophthalmology Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Ophthalmology Physician share within Washington

Specialty board-certification context

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

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

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

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

DELFRED DIEHL, M.D., FRCSC is a Ophthalmology Physician provider practicing in SEATTLE, Washington, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: M.D., FRCSC. NPI: 1952468274. 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.

DELFRED DIEHL, M.D., FRCSC appears in the CMS NPPES registry as a Ophthalmology Physician provider holding M.D., FRCSC credentials at 310 15TH AVE E, SEATTLE, WA, 98112, with a listed phone of (206) 326-3131. NPI 1952468274 was issued on 01/03/2007. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what DIEHL 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 56 prescription claims written by this provider, covering 33 Medicare beneficiaries and totaling roughly $3K 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.

Ophthalmology Physician is a mid-sized specialty nationwide, with 22,090 enrolled providers across 56 states and an average of 1,420 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

310 15TH AVE E
SEATTLE, WA 98112

Provider Details

NPI 1952468274
Specialty Ophthalmology Physician
Credentials M.D., FRCSC
Gender Male
NPI Issued 01/03/2007

License & disciplinary context — Washington WMC 2023 annual report

Aggregate state board data only — NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~34K Washington medical licensees in 2023 — they are NOT specific to DELFRED DIEHL, M.D., FRCSC. To verify DELFRED DIEHL, M.D., FRCSC's current license status, search the WMC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

88
Total board actions, Washington 2023
Across 85 cases
2.59
Actions per 1,000 licensees
Washington statewide rate
probation
Most common action type
31 cases

WMC publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the Washington disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Medicare Part D Prescribing Data

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

56
Total Claims
$3K
Total Drug Cost
33
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
119
Total Day Supply
3,521
Generic Drug Cost
$2K

Patient Demographics

Average Patient Age
76.9 years
Avg HCC Risk Score
0.99
Gender Split
52% female / 48% 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
Latanoprost
21

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

Ophthalmology Physician Overview

How DELFRED DIEHL, M.D., FRCSC fits within the Ophthalmology Physician landscape nationally.

22,090
Ophthalmology Physician Providers in US
56
States with Ophthalmology Physician
1,420
Avg Claims per Provider

DELFRED DIEHL, M.D., FRCSC's 56 claims are below the specialty average of 1,420.

Nearby Ophthalmology Physician Providers in Washington

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

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

Frequently Asked Questions

What is DELFRED DIEHL, M.D., FRCSC's specialty?
DELFRED DIEHL, M.D., FRCSC specializes in Ophthalmology Physician and practices in SEATTLE, Washington. Credentials: M.D., FRCSC.
How much does DELFRED DIEHL, M.D., FRCSC prescribe under Medicare Part D?
In 2023, DELFRED DIEHL, M.D., FRCSC wrote 56 Medicare Part D claims totaling $3K in drug costs for 33 beneficiaries.
Where is DELFRED DIEHL, M.D., FRCSC located?
DELFRED DIEHL, M.D., FRCSC is located at 310 15TH AVE E, SEATTLE, WA, 98112. Phone: (206) 326-3131.
What is DELFRED DIEHL, M.D., FRCSC's NPI number?
DELFRED DIEHL, M.D., FRCSC's National Provider Identifier (NPI) is 1952468274, issued on 01/03/2007.
How many Ophthalmology Physician providers are there in the US?
There are 22,090 Ophthalmology Physician providers across 56 states in the US. The average Ophthalmology Physician provider writes 1,420 Medicare Part D claims per year.
What drugs does DELFRED DIEHL, M.D., FRCSC prescribe most often?
Based on 2023 Medicare Part D data, DELFRED DIEHL, M.D., FRCSC's most frequently prescribed drugs include Latanoprost. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does DELFRED DIEHL, M.D., FRCSC accept Medicare?
DELFRED DIEHL, M.D., FRCSC appears in CMS Medicare data with 56 Part D claims and 33 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify DELFRED DIEHL, M.D., FRCSC's credentials?
DELFRED DIEHL, M.D., FRCSC's NPI is 1952468274 with credentials M.D., FRCSC. 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