NPI registry status
Active
2026 NPPES data Infectious Disease Physician NPI 1639339484 M.D.
Verify on CMS → Chad Duffalo, M.D.
Infectious Disease Physician in Newark, Delaware.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 8,537 in Infectious Disease 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
670
Medicare Part D claims · 117 beneficiaries · Infectious Disease Physician avg: 807
Generic prescribing
71%
generic claims · 29% brand-name · higher generic rates reduce patient out-of-pocket costs
MIPS score
75/100
CMS neutral threshold · no category scores published
Industry payments
$419.12
17 payments · CMS Open Payments (Sunshine Act)
Source: CMS Medicare Part D Prescriber Public Use File, 2024
What the federal data shows
Chad Duffalo, M.D. carries the neutral CMS MIPS final score of 75/100, assigned where no category was scored - and filed 670 Medicare Part D claims in 2024.
- 75/100
- CMS neutral score · not measured
- 670
- Part D claims, 2024
- 71%
- 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.
Federal trust snapshot
What official records show about Chad Duffalo, M.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 1639339484), first enumerated 06/16/2008.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 670 Medicare Part D prescription claims in the 2023 CMS public use file — indicates active Medicare prescribing participation.
Source: CMS Part D Prescriber PUF
- Reported
CMS quality reporting (MIPS)
CMS assigned a neutral MIPS final score of 75/100 where no performance category was scored — not a measured quality rank.
Source: CMS Quality Payment Program
- Reported
Board certification signal
Heuristic suggests board-certified status based on ABMS-eligible specialty taxonomy plus active CMS participation signals — not a direct ABMS verification.
- Reported
Hospital affiliations
1 CMS Care Compare hospital affiliation on record — practice footprint from the Doctors and Clinicians file.
Source: CMS Care Compare
- Reported
Industry payment transparency
$419.12 in reported industry payments (17 transfers) in 2024 under the federal Sunshine Act — disclosed transfers of value, not a quality rating.
Source: CMS Open Payments
- 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 1639339484 · Infectious Disease Physician
NPI-10 · ENUM-MID · TAX-MID · MIPS-NEUTRAL · RX-LIGHT · BOOK-THIN · PHOTO-ENUM
- NPI-10 1639339484
- ENUM-MID 2008
- TAX-MID 9K Infectious Disease
- MIPS-NEUTRAL 75/100
- RX-LIGHT 670
- BOOK-THIN 25 in Delaware
- PHOTO-ENUM Benjamin Zaniello · 2008
Chad Duffalo, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
670 ≥ 68th percentile 68% 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
✓
Board certification likely (heuristic, not verified)
Chad Duffalo, M.D. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + MIPS quality reporting + 1 hospital affiliation - 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 Chad Duffalo, M.D.?
CMS neutral score, not measuredPrimary specialty
Infectious Disease Physician
Medicare Part D claims
670 17% vs specialty avg
MIPS final score
75/100
Specialty distribution in Delaware
How Infectious Disease Physician compares to other specialties among Delaware providers
MIPS score not measured
CMS assigned a neutral 75/100 threshold
CMS did not publish any Quality, Cost, Promoting Interoperability, or Improvement Activities category score for this clinician. This administrative threshold is not comparable with the national average of clinicians whose MIPS score was measured.
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 | 1639339484 |
|---|---|
| Specialty | Infectious Disease Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 06/16/2008 |
CMS Quality Score (MIPS)
Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.
75
Final Score
CMS neutral threshold · not measured
Reporting: Group practice
Hospital and facility affiliations
Facilities where Chad Duffalo, M.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.
Infectious Disease Consultants PA
Elkton, MD
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 Chad Duffalo, M.D.. Source: openpaymentsdata.cms.gov.
Total received
$419
Largest payer
ViiV Healthcare Company
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.
Brand vs generic prescribing mix · Above average
Chad Duffalo, M.D. - brand share 29.0%
Infectious Disease Physician average
29% brand-name claims vs 71% generic, on 670 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.
670
Total Claims
$780K
Total Drug Cost
117
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 758
- Total Day Supply
- 17,256
- Brand vs Generic
- 29% brand / 71% generic
- Brand Drug Cost
- $712K
- Generic Drug Cost
- $69K
- Antibiotic Claims
- 391
Patient Demographics
- Average Patient Age
- 70.7 years
- Avg HCC Risk Score
- 2.86
- Gender Split
- 48% female / 52% male
- Age Distribution
- <65: 24, 65-74: 49, 75-84: 31, 85+: 13
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2024. Based on Medicare Part D data only.
What Chad Duffalo, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2024
- Azithromycin
Azithromycin
47 claims
- Vancomycin Hcl
Vancomycin Hcl
46 claims
- Amoxicillin-Clavul…
Amoxicillin-Clavulanate Potass
40 claims
- Odefsey
Odefsey
35 claims
- Genvoya
Genvoya
34 claims
- Sulfamethoxazole-T…
Sulfamethoxazole-Trimethoprim
34 claims
- Cephalexin
Cephalexin
31 claims
- Rifampin
Rifampin
26 claims
| Drug | Claims |
|---|---|
| Azithromycin | 47 |
| Vancomycin Hcl | 46 |
| Amoxicillin-Clavulanate Potass Amoxicillin/Potassium Clav | 40 |
| Odefsey Emtricitab/Rilpiviri/Tenof Ala | 35 |
| Genvoya Elviteg/Cob/Emtri/Tenof Alafen | 34 |
| Sulfamethoxazole-Trimethoprim Sulfamethoxazole/Trimethoprim | 34 |
| Cephalexin | 31 |
| Rifampin | 26 |
| Descovy Emtricitabine/Tenofov Alafenam | 21 |
| Tivicay Dolutegravir Sodium | 21 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Infectious Disease Physician Overview
How Chad Duffalo, M.D. fits within the Infectious Disease Physician landscape nationally.
8,537
Infectious Disease Physician Providers in US
54
States with Infectious Disease Physician
807
Avg Claims per Provider
Chad Duffalo, M.D.'s 670 claims are below the specialty average of 807.
Nationwide Infectious Disease Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Duffalo, both outside Delaware so the neighborhoods are not geographic containment.
Similar MIPS final score
Nearest same-specialty clinicians by CMS MIPS final score (75 here).
Same NPPES enumeration year (2008)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Infectious Disease Physician Providers in Delaware
Other clinicians with the same primary specialty enrolled in Delaware, drawn from the same CMS NPPES roster as Duffalo.
One of 25 Infectious Disease Physician providers enrolled in Delaware, 5 are shown here.
Dr. Alfred Bacon
MD
Newark, DE
Dr. William Chasanov
D.O.
Lewes, DE
Dr. Jimmy Chua
M.D.
Lewes, DE
Dr. David Cohen
M.D.
Newark, DE
Dr. Marci Drees
M.D.
Smyrna, DE
Compare Infectious Disease Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is Chad Duffalo, M.D.'s specialty? ▼
Chad Duffalo, M.D. specializes in Infectious Disease Physician and practices in Newark, Delaware. Credentials: M.D..
How much does Chad Duffalo, M.D. prescribe under Medicare Part D? ▼
In 2024, Chad Duffalo, M.D. wrote 670 Medicare Part D claims totaling $780K in drug costs for 117 beneficiaries.
What is Chad Duffalo, M.D.'s Medicare quality score? ▼
Chad Duffalo, M.D. has a CMS MIPS Final Score of 75/100. CMS published no Quality, Promoting Interoperability, Improvement Activity or Cost score for this clinician, so the final score is the neutral performance threshold CMS assigns rather than a measured result. The average MIPS Final Score across the 454,083 clinicians with at least one published category score is 83.5; clinicians whose score CMS assigned without scoring any category are excluded from that average. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is Chad Duffalo, M.D. located? ▼
Chad Duffalo, M.D. is located at 537 STANTON CHRISTIANA RD, Newark, DE, 19713. Phone: (302) 994-9692.
What is Chad Duffalo, M.D.'s NPI number? ▼
Chad Duffalo, M.D.'s National Provider Identifier (NPI) is 1639339484, issued on 06/16/2008.
Does Chad Duffalo, M.D. prescribe more brand-name or generic drugs? ▼
Chad Duffalo, M.D.'s prescribing is 29% brand-name and 71% generic drugs by claim count, with $712K in brand drug costs.
How many Infectious Disease Physician providers are there in the US? ▼
There are 8,537 Infectious Disease Physician providers across 54 states in the US. The average Infectious Disease Physician provider writes 807 Medicare Part D claims per year.
What drugs does Chad Duffalo, M.D. prescribe most often? ▼
Based on 2024 Medicare Part D data, Chad Duffalo, M.D.'s most frequently prescribed drugs include Azithromycin, Vancomycin Hcl, Amoxicillin-Clavulanate Potass. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Chad Duffalo, M.D. accept Medicare? ▼
Chad Duffalo, M.D. appears in CMS Medicare data with 670 Part D claims and 117 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Chad Duffalo, M.D.'s credentials? ▼
Chad Duffalo, M.D.'s NPI is 1639339484 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 (2024). 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 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.