NPI registry status
Active
2026 NPPES data Sports Medicine (Internal Medicine) Physician NPI 1821258062 DO
Verify on CMS → John McMahon, DO
Sports Medicine (Internal Medicine) Physician in Portsmouth, New Hampshire.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 295 in Sports Medicine (Internal Medicine) 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
85
Medicare Part D claims · 46 beneficiaries · Sports Medicine (Internal Medicine) Physician avg: 1K
MIPS score
77.6/100
▼ 5 pts below national avg 83.1 · Above neutral
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
John McMahon, DO reported a CMS MIPS final score of 77.6/100 - below the 83.1 national average - and filed 85 Medicare Part D claims in 2023.
- 77.6/100
- MIPS score · -5 vs avg
- 85
- Part D claims, 2023
- 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.
John McMahon, DO's MIPS score vs every scored U.S. clinician
CMS Merit-based Incentive Payment System (MIPS) final score, 2023, the federal quality measure
78 24th percentile higher than 24% of 477,587 scored providers
Each bar is a band; taller bars hold more scored providers. 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 Merit-based Incentive Payment System (MIPS) · 2023
Where John McMahon, DO sits
This provider among sports medicine (internal medicine) physician peers
Across the 68 sports medicine (internal medicine) physician providers who report both Medicare Part D prescribing and a MIPS quality score, John McMahon, DO writes more Part D claims than 7% of them and scores higher on MIPS quality than 26% - placing this provider in the lower-volume, lower-quality quadrant. Volume reflects patient-panel size and specialty, not quality; the two axes are independent.
Part D claim volume vs MIPS quality, by specialty percentile
Each dot is one sports medicine (internal medicine) physician peer from a representative sample of 60; the gold marker is John McMahon, DO. Source: CMS Medicare Part D Prescriber data and the CMS Merit-based Incentive Payment System, 2023.
✓
Board certification likely (heuristic, not verified)
John McMahon, DO 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 John McMahon, DO?
Below national averagePrimary specialty
Sports Medicine (Internal Medicine) Physician
Medicare Part D claims
85 93% vs specialty avg
MIPS final score
77.6/100 5.5 pts vs avg
Specialty distribution in New Hampshire
How Sports Medicine (Internal Medicine) Physician compares to other specialties among New Hampshire providers
Medicare quality performance, MIPS
John McMahon, DO's 2023 MIPS final score plotted against the Sports Medicine (Internal Medicine) Physician national average
- MIPS Final Score
- 77.6/100
- vs 83.1 national avg · 2023 performance year
MIPS final score (Sports Medicine (Internal Medicine) Physician) - 77.6/100 vs national avg 83.1
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).
John McMahon, DO appears in the CMS NPPES registry as a Sports Medicine (Internal Medicine) Physician provider holding DO credentials at 1900 LAFAYETTE RD, Portsmouth, NH, 03801, with a listed phone of (603) 431-1121. NPI 1821258062 was issued on 06/11/2008.
Medicare Part D records for calendar year 2023 show 85 prescription claims written by this provider, covering 46 Medicare beneficiaries and totaling roughly $851 in drug spend, with an opioid prescribing rate of 34.1%. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 77.6/100 for the 2023 performance year, compared with the national average of 83.1.
Sports Medicine (Internal Medicine) Physician is a narrow specialty nationwide, with 295 enrolled providers across 43 states and an average of 1,267 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 | 1821258062 |
|---|---|
| Specialty | Sports Medicine (Internal Medicine) Physician |
| Credentials | DO |
| Gender | Male |
| NPI Issued | 06/11/2008 |
CMS Quality Score (MIPS)
Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.
77.6308
Final Score
Avg: 83.1
25.436
Cost
100
Promoting Interoperability
Reporting: Individual
Hospital and facility affiliations
Facilities where John McMahon, 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.
Sportsmedicine Atlantic Orthopaedics PA
Dover, NH
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2023.
85
Total Claims
$851
Total Drug Cost
46
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 93
- Total Day Supply
- 1,533
- Brand Drug Cost
- $0
- Generic Drug Cost
- $851
- Opioid Claims
- 29 (34.1% rate)
Patient Demographics
- Average Patient Age
- 73.4 years
- Avg HCC Risk Score
- 0.78
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What John McMahon, DO prescribes most
Top Medicare Part D drugs by claim count, 2023
- Prednisone
Prednisone
27 claims
- Tramadol Hcl
Tramadol Hcl
21 claims
- Meloxicam
Meloxicam
14 claims
| Drug | Claims |
|---|---|
| Prednisone | 27 |
| Tramadol Hcl | 21 |
| Meloxicam | 14 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
More Sports Medicine (Internal Medicine) Physician in NH →
All providers in New Hampshire →
Compare specialties →
Sports Medicine (Internal Medicine) Physician Overview
How John McMahon, DO fits within the Sports Medicine (Internal Medicine) Physician landscape nationally.
295
Sports Medicine (Internal Medicine) Physician Providers in US
43
States with Sports Medicine (Internal Medicine) Physician
1,267
Avg Claims per Provider
John McMahon, DO's 85 claims are below the specialty average of 1,267.
Nearby Sports Medicine (Internal Medicine) Physician Providers in New Hampshire
Other clinicians with the same primary specialty enrolled in New Hampshire, drawn from the same CMS NPPES roster as McMahon.
Compare Sports Medicine (Internal Medicine) Physician 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 New Hampshire medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Sports Medicine (Internal Medicine) Physician 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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Medical Specialties Explained
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Understanding Medicare Claims Data
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Frequently Asked Questions
What is John McMahon, DO's specialty? ▼
John McMahon, DO specializes in Sports Medicine (Internal Medicine) Physician and practices in Portsmouth, New Hampshire. Credentials: DO.
How much does John McMahon, DO prescribe under Medicare Part D? ▼
In 2023, John McMahon, DO wrote 85 Medicare Part D claims totaling $851 in drug costs for 46 beneficiaries.
What is John McMahon, DO's Medicare quality score? ▼
John McMahon, DO has a CMS MIPS Final Score of 77.6/100, Cost: 25.4. The national average MIPS Final Score is 83.1. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is John McMahon, DO located? ▼
John McMahon, DO is located at 1900 LAFAYETTE RD, Portsmouth, NH, 03801. Phone: (603) 431-1121.
What is John McMahon, DO's NPI number? ▼
John McMahon, DO's National Provider Identifier (NPI) is 1821258062, issued on 06/11/2008.
Does John McMahon, DO prescribe opioids? ▼
Yes, John McMahon, DO had 29 opioid claims in 2023 with an opioid prescribing rate of 34.1%.
How many Sports Medicine (Internal Medicine) Physician providers are there in the US? ▼
There are 295 Sports Medicine (Internal Medicine) Physician providers across 43 states in the US. The average Sports Medicine (Internal Medicine) Physician provider writes 1,267 Medicare Part D claims per year.
What drugs does John McMahon, DO prescribe most often? ▼
Based on 2023 Medicare Part D data, John McMahon, DO's most frequently prescribed drugs include Prednisone, Tramadol Hcl, Meloxicam. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does John McMahon, DO accept Medicare? ▼
John McMahon, DO appears in CMS Medicare data with 85 Part D claims and 46 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify John McMahon, DO's credentials? ▼
John McMahon, DO's NPI is 1821258062 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
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.
- 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 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.