2026 NPPES data Sleep Medicine (Internal Medicine) Physician NPI 1366860421 DO
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DAVID DELAPP, DO

Sleep Medicine (Internal Medicine) Physician in WINFIELD, Illinois. 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
1K
Medicare Part D claims · 348 beneficiaries · Sleep Medicine (Internal Medicine) Physician avg: 1K
Generic prescribing
34%
generic claims · 66% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$92.21
2 payments · CMS Open Payments (Sunshine Act)
What the federal data reveals: DAVID DELAPP, DO is a Sleep Medicine (Internal Medicine) Physician ([object Object]) practicing in WINFIELD, Illinois with a Medicare Part D prescribing footprint of 1K claims across 348 beneficiaries — 66% brand-name prescribing . Industry payments of $92.21 across 2 transactions are disclosed under CMS Open Payments (Sunshine Act).

What stands out: DAVID DELAPP, DO filed 1,428 Medicare Part D claims in 2023 across WINFIELD, Illinois. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

DAVID DELAPP, DO practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation — signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).

DAVID DELAPP, DO at a glance

Quality data not reported

NPI registry status

Active

Issued 04/04/2014

NPI 1366860421

Primary specialty

Sleep Medicine (Internal Medicine) Physician

Niche

857 US NPIs in this specialty

Medicare Part D claims

1,428 9% vs specialty avg

2023 prescription claims

Specialty avg: 1,310

Specialty distribution in Illinois

How Sleep Medicine (Internal Medicine) Physician compares to other specialties among Illinois providers

Illinois providers

Sleep Medicine (Internal Medicine) Physician share within Illinois

1. Sleep Medicine (Internal Medicine) Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Sleep Medicine (Internal Medicine) Physician share within Illinois

Specialty board-certification context

Estimated specialty board-certified rate — Sleep Medicine (Internal Medicine) Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Sleep Medicine (Internal Medicine) Physician ABMS/AOA estimate

Est. board-certified rate (Sleep Medicine (Internal Medicine) Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Sleep Medicine (Internal Medicine) 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).

DAVID DELAPP, DO is a Sleep Medicine (Internal Medicine) Physician provider practicing in WINFIELD, Illinois, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: DO. NPI: 1366860421. 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.

DAVID DELAPP, DO appears in the CMS NPPES registry as a Sleep Medicine (Internal Medicine) Physician provider holding DO credentials at 25 N WINFIELD RD STE 204, WINFIELD, IL, 60190, with a listed phone of (630) 232-0202. NPI 1366860421 was issued on 04/04/2014. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what DELAPP 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 1,428 prescription claims written by this provider, covering 348 Medicare beneficiaries and totaling roughly $633K in drug spend, split 66% brand-name and 34% 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.

Sleep Medicine (Internal Medicine) Physician is a narrow specialty nationwide, with 857 enrolled providers across 52 states and an average of 1,310 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

25 N WINFIELD RD STE 204
WINFIELD, IL 60190

Provider Details

NPI 1366860421
Specialty Sleep Medicine (Internal Medicine) Physician
Credentials DO
Gender Male
NPI Issued 04/04/2014

Hospital and facility affiliations

Facilities where DAVID DELAPP, DO 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.

CENTRAL DUPAGE PHYSICIAN GROUP
WINFIELD, IL

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

Industry payments received (2024) — CMS Open Payments transparency data

The federal Physician Payments Sunshine Act (part of the Affordable Care Act) requires drug and medical-device manufacturers + group purchasing organizations to publicly report payments and other transfers of value to physicians and teaching hospitals. The data below covers 2024 for DAVID DELAPP, DO. Source: openpaymentsdata.cms.gov.

Total received

$92

Largest payer

Inspire Medical Systems, Inc.

Most common payment type

Food and Beverage

Industry payments are not necessarily indicators of bias — they include research funding, consulting fees for evidence-based work, royalties for inventions, food at conferences, and similar items. The disclosure exists for transparency. Read our methodology for how we interpret this data.

License & disciplinary context — Illinois IDFPR 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 ~42K Illinois medical licensees in 2023 — they are NOT specific to DAVID DELAPP, DO. To verify DAVID DELAPP, DO's current license status, search the IDFPR public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

106
Total board actions, Illinois 2023
Across 103 cases
2.52
Actions per 1,000 licensees
Illinois statewide rate
probation
Most common action type
38 cases

IDFPR 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 Illinois disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Brand vs generic prescribing mix · Brand-heavy

DAVID DELAPP, DO — brand share 66.0%
Specialty average (est.)

66% brand-name claims vs 34% generic, on 1,428 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.

1,428
Total Claims
$633K
Total Drug Cost
348
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
2,152
Total Day Supply
59,694
Brand vs Generic
66% brand / 34% generic
Brand Drug Cost
$584K
Antibiotic Claims
59

Patient Demographics

Average Patient Age
74.6 years
Avg HCC Risk Score
1.64
Gender Split
58% female / 42% male
Age Distribution
<65: 25, 65-74: 142, 75-84: 138, 85+: 43

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Albuterol Sulfate Hfa
Albuterol Sulfate
230
Trelegy Ellipta
Fluticasone/Umeclidin/Vilanter
127
Breo Ellipta
Fluticasone/Vilanterol
110
Prednisone
95
Symbicort
Budesonide/Formoterol Fumarate
67
Anoro Ellipta
Umeclidinium Brm/Vilanterol Tr
61
Fluticasone Propionate
51
Incruse Ellipta
Umeclidinium Bromide
46
Stiolto Respimat
Tiotropium Br/Olodaterol Hcl
43
Ventolin Hfa
Albuterol Sulfate
38

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

Sleep Medicine (Internal Medicine) Physician Overview

How DAVID DELAPP, DO fits within the Sleep Medicine (Internal Medicine) Physician landscape nationally.

857
Sleep Medicine (Internal Medicine) Physician Providers in US
52
States with Sleep Medicine (Internal Medicine) Physician
1,310
Avg Claims per Provider

DAVID DELAPP, DO's 1,428 claims are above the specialty average of 1,310.

Nearby Sleep Medicine (Internal Medicine) Physician Providers in Illinois

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

Compare Sleep Medicine (Internal Medicine) Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is DAVID DELAPP, DO's specialty?
DAVID DELAPP, DO specializes in Sleep Medicine (Internal Medicine) Physician and practices in WINFIELD, Illinois. Credentials: DO.
How much does DAVID DELAPP, DO prescribe under Medicare Part D?
In 2023, DAVID DELAPP, DO wrote 1,428 Medicare Part D claims totaling $633K in drug costs for 348 beneficiaries.
Where is DAVID DELAPP, DO located?
DAVID DELAPP, DO is located at 25 N WINFIELD RD STE 204, WINFIELD, IL, 60190. Phone: (630) 232-0202.
What is DAVID DELAPP, DO's NPI number?
DAVID DELAPP, DO's National Provider Identifier (NPI) is 1366860421, issued on 04/04/2014.
Does DAVID DELAPP, DO prescribe more brand-name or generic drugs?
DAVID DELAPP, DO's prescribing is 66% brand-name and 34% generic drugs by claim count, with $584K in brand drug costs.
How many Sleep Medicine (Internal Medicine) Physician providers are there in the US?
There are 857 Sleep Medicine (Internal Medicine) Physician providers across 52 states in the US. The average Sleep Medicine (Internal Medicine) Physician provider writes 1,310 Medicare Part D claims per year.
What drugs does DAVID DELAPP, DO prescribe most often?
Based on 2023 Medicare Part D data, DAVID DELAPP, DO's most frequently prescribed drugs include Albuterol Sulfate Hfa, Trelegy Ellipta, Breo Ellipta. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does DAVID DELAPP, DO accept Medicare?
DAVID DELAPP, DO appears in CMS Medicare data with 1,428 Part D claims and 348 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify DAVID DELAPP, DO's credentials?
DAVID DELAPP, DO's NPI is 1366860421 with credentials DO. 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