NPI registry status
Active
2026 NPPES data Nurse Practitioner NPI 1285250118 APN
Verify on CMS → Karen Mather, APN
Nurse Practitioner in Bethany Beach, 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 87,700 in Nurse Practitioner, 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
3K
Medicare Part D claims · 489 beneficiaries · Nurse Practitioner avg: 1K
Generic prescribing
93%
generic claims · 7% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$941.45
40 payments · CMS Open Payments (Sunshine Act)
Source: CMS Medicare Part D Prescriber Public Use File, 2023
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
Karen Mather, APN filed 2,865 Medicare Part D claims in 2023 as a Nurse Practitioner in Bethany Beach, Delaware, prescribing 93% generic.
- 3K
- Part D claims, 2023
- 93%
- generic prescribing
- $941.45
- industry payments (Sunshine Act)
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.
Karen Mather, APN's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
2,865 Top 12% higher than 88% of 1,370,886 prescribers
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.
Source CMS Medicare Part D Prescriber Public Use File · 2023
What does the federal data show about Karen Mather, APN?
Quality data not reportedPrimary specialty
Nurse Practitioner
Medicare Part D claims
2,865 164% vs specialty avg
Specialty distribution in Delaware
How Nurse Practitioner compares to other specialties among Delaware 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 Nurse Practitioner. 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).
Karen Mather, APN appears in the CMS NPPES registry as a Nurse Practitioner provider holding APN credentials at 33188 COASTAL HWY UNIT 4, Bethany Beach, DE, 19930, with a listed phone of (302) 537-1100. NPI 1285250118 was issued on 06/16/2020.
Medicare Part D records for calendar year 2023 show 2,865 prescription claims written by this provider, covering 489 Medicare beneficiaries and totaling roughly $163K in drug spend, split 7% brand-name and 93% generic by claim count, with an opioid prescribing rate of 5.7%.
Nurse Practitioner is a high-volume specialty nationwide, with 87,700 enrolled providers across 56 states and an average of 1,084 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
Provider Details
| NPI | 1285250118 |
|---|---|
| Specialty | Nurse Practitioner |
| Credentials | APN |
| Gender | Female |
| NPI Issued | 06/16/2020 |
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 Karen Mather, APN. Source: openpaymentsdata.cms.gov.
Total received
$941
Largest payer
Eisai 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.
Brand vs generic prescribing mix · Generic-heavy
Karen Mather, APN - brand share 7.0%
Nurse Practitioner average
7% brand-name claims vs 93% generic, on 2,865 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.
2,865
Total Claims
$163K
Total Drug Cost
489
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 5,605
- Total Day Supply
- 154,223
- Brand vs Generic
- 7% brand / 93% generic
- Brand Drug Cost
- $114K
- Generic Drug Cost
- $49K
- Opioid Claims
- 163 (5.7% rate)
- Antibiotic Claims
- 256
Patient Demographics
- Average Patient Age
- 72.5 years
- Avg HCC Risk Score
- 0.96
- Gender Split
- 57% female / 43% male
- Age Distribution
- <65: 42, 65-74: 256, 75-84: 143, 85+: 48
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Karen Mather, APN prescribes most
Top Medicare Part D drugs by claim count, 2023
- Tramadol Hcl
Tramadol Hcl
160 claims
- Alprazolam
Alprazolam
134 claims
- Rosuvastatin Calcium
Rosuvastatin Calcium
125 claims
- Atorvastatin Calcium
Atorvastatin Calcium
98 claims
- Zolpidem Tartrate
Zolpidem Tartrate
85 claims
- Lisinopril
Lisinopril
83 claims
- Levothyroxine Sodium
Levothyroxine Sodium
73 claims
- Azithromycin
Azithromycin
67 claims
| Drug | Claims |
|---|---|
| Tramadol Hcl | 160 |
| Alprazolam | 134 |
| Rosuvastatin Calcium | 125 |
| Atorvastatin Calcium | 98 |
| Zolpidem Tartrate | 85 |
| Lisinopril | 83 |
| Levothyroxine Sodium | 73 |
| Azithromycin | 67 |
| Amlodipine Besylate | 66 |
| Methylprednisolone | 62 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Nurse Practitioner Overview
How Karen Mather, APN fits within the Nurse Practitioner landscape nationally.
87,700
Nurse Practitioner Providers in US
56
States with Nurse Practitioner
1,084
Avg Claims per Provider
Karen Mather, APN's 2,865 claims are above the specialty average of 1,084.
Nearby Nurse Practitioner Providers in Delaware
Other clinicians with the same primary specialty enrolled in Delaware, drawn from the same CMS NPPES roster as Mather.
Dr. Hannah Abinteh
NP
Wilmington, DE
Dr. Jittu Abraham
NP
Newark, DE
Dr. Sarah Abugah
PMHNP
Middletown, DE
Davi-Lue Achu
Wilmington, DE
Vanessa Adams
Lewes, DE
Compare Nurse Practitioner nationally: see state-by-state distribution →
Before you book an appointment
Use this federal record as your verification checklist, not as a recommendation.
- Confirm the NPI record is current in the official CMS registry, providers update their own NPPES details, and moves can lag. Verify this NPI
- Check the active license and any disciplinary history with the Delaware medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Nurse Practitioner peer on Medicare volume and prescribing patterns. Compare providers
Medicare Part D and MIPS figures describe practice patterns in federal programs only, they are not quality ratings, and PlainDoctor does not rate, rank, or recommend providers.
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Frequently Asked Questions
What is Karen Mather, APN's specialty? ▼
Karen Mather, APN specializes in Nurse Practitioner and practices in Bethany Beach, Delaware. Credentials: APN.
How much does Karen Mather, APN prescribe under Medicare Part D? ▼
In 2023, Karen Mather, APN wrote 2,865 Medicare Part D claims totaling $163K in drug costs for 489 beneficiaries.
Where is Karen Mather, APN located? ▼
Karen Mather, APN is located at 33188 COASTAL HWY UNIT 4, Bethany Beach, DE, 19930. Phone: (302) 537-1100.
What is Karen Mather, APN's NPI number? ▼
Karen Mather, APN's National Provider Identifier (NPI) is 1285250118, issued on 06/16/2020.
Does Karen Mather, APN prescribe more brand-name or generic drugs? ▼
Karen Mather, APN's prescribing is 7% brand-name and 93% generic drugs by claim count, with $114K in brand drug costs.
Does Karen Mather, APN prescribe opioids? ▼
Yes, Karen Mather, APN had 163 opioid claims in 2023 with an opioid prescribing rate of 5.7%.
How many Nurse Practitioner providers are there in the US? ▼
There are 87,700 Nurse Practitioner providers across 56 states in the US. The average Nurse Practitioner provider writes 1,084 Medicare Part D claims per year.
What drugs does Karen Mather, APN prescribe most often? ▼
Based on 2023 Medicare Part D data, Karen Mather, APN's most frequently prescribed drugs include Tramadol Hcl, Alprazolam, Rosuvastatin Calcium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Karen Mather, APN accept Medicare? ▼
Karen Mather, APN appears in CMS Medicare data with 2,865 Part D claims and 489 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Karen Mather, APN's credentials? ▼
Karen Mather, APN's NPI is 1285250118 with credentials APN. 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 (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
Compiled from official public sources by the PlainDoctor editorial team.
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 May 2026.