NPI registry status
Active
2026 NPPES data Hospitalist Physician NPI 1467403345 MD
Verify on CMS → Joan McMahon, MD
Hospitalist Physician in Lewistown, Montana.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 16,938 in Hospitalist 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
443
Medicare Part D claims · 90 beneficiaries · Hospitalist Physician avg: 888
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
Joan McMahon, MD filed 443 Medicare Part D claims in 2023 as a Hospitalist Physician in Lewistown, Montana.
- 443
- 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.
Joan McMahon, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
443 Top 38% higher than 62% 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
✓
Board certification likely (heuristic, not verified)
Joan McMahon, MD 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).
What does the federal data show about Joan McMahon, MD?
Quality data not reportedPrimary specialty
Hospitalist Physician
Medicare Part D claims
443 50% vs specialty avg
Specialty distribution in Montana
How Hospitalist Physician compares to other specialties among Montana 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 Hospitalist Physician. 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).
Joan McMahon, MD appears in the CMS NPPES registry as a Hospitalist Physician provider holding MD credentials at 408 WENDELL AVE, Lewistown, MT, 59457, with a listed phone of (406) 535-1502. NPI 1467403345 was issued on 05/15/2006.
Medicare Part D records for calendar year 2023 show 443 prescription claims written by this provider, covering 90 Medicare beneficiaries and totaling roughly $30K in drug spend.
Hospitalist Physician is a mid-sized specialty nationwide, with 16,938 enrolled providers across 54 states and an average of 888 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 | 1467403345 |
|---|---|
| Specialty | Hospitalist Physician |
| Credentials | MD |
| Gender | Female |
| NPI Issued | 05/15/2006 |
Hospital and facility affiliations
Facilities where Joan McMahon, MD 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 Montana Medical Facilities Inc
Lewistown, MT
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.
443
Total Claims
$30K
Total Drug Cost
90
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 629
- Total Day Supply
- 17,315
- Generic Drug Cost
- $4K
- Antibiotic Claims
- 31
Patient Demographics
- Average Patient Age
- 73.8 years
- Avg HCC Risk Score
- 1.19
- Gender Split
- 59% female / 41% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Joan McMahon, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Lisinopril
Lisinopril
40 claims
- Atorvastatin Calcium
Atorvastatin Calcium
33 claims
- Albuterol Sulfate …
Albuterol Sulfate Hfa
24 claims
- Levothyroxine Sodium
Levothyroxine Sodium
23 claims
- Simvastatin
Simvastatin
17 claims
- Potassium Chloride 14
Potassium Chloride
14 claims
- Fluticasone Propio… 13
Fluticasone Propionate
13 claims
- Symbicort 13
Symbicort
13 claims
| Drug | Claims |
|---|---|
| Lisinopril | 40 |
| Atorvastatin Calcium | 33 |
| Albuterol Sulfate Hfa Albuterol Sulfate | 24 |
| Levothyroxine Sodium | 23 |
| Simvastatin | 17 |
| Potassium Chloride | 14 |
| Fluticasone Propionate | 13 |
| Symbicort Budesonide/Formoterol Fumarate | 13 |
| Doxazosin Mesylate | 12 |
| Finasteride | 12 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Hospitalist Physician Overview
How Joan McMahon, MD fits within the Hospitalist Physician landscape nationally.
16,938
Hospitalist Physician Providers in US
54
States with Hospitalist Physician
888
Avg Claims per Provider
Joan McMahon, MD's 443 claims are below the specialty average of 888.
Nearby Hospitalist Physician Providers in Montana
Other clinicians with the same primary specialty enrolled in Montana, drawn from the same CMS NPPES roster as McMahon.
Dr. Kylie Abeson
MD, MPH
Billings, MT
Dr. Rebecca Anderson
MD
Missoula, MT
Dr. Sean Banks
DO
Great Falls, MT
Dr. Shelly Basye
M.D.
Billings, MT
Dr. Jason Bechard
MD
Kalispell, MT
Compare Hospitalist 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 Montana medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Hospitalist 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.
Healthcare Guides
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Medical Specialties Explained
Who treats what and how specialties differ
Understanding Medicare Claims Data
What prescribing data reveals about a provider
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How insurance networks affect your costs
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Explore Montana
Frequently Asked Questions
What is Joan McMahon, MD's specialty? ▼
Joan McMahon, MD specializes in Hospitalist Physician and practices in Lewistown, Montana. Credentials: MD.
How much does Joan McMahon, MD prescribe under Medicare Part D? ▼
In 2023, Joan McMahon, MD wrote 443 Medicare Part D claims totaling $30K in drug costs for 90 beneficiaries.
Where is Joan McMahon, MD located? ▼
Joan McMahon, MD is located at 408 WENDELL AVE, Lewistown, MT, 59457. Phone: (406) 535-1502.
What is Joan McMahon, MD's NPI number? ▼
Joan McMahon, MD's National Provider Identifier (NPI) is 1467403345, issued on 05/15/2006.
How many Hospitalist Physician providers are there in the US? ▼
There are 16,938 Hospitalist Physician providers across 54 states in the US. The average Hospitalist Physician provider writes 888 Medicare Part D claims per year.
What drugs does Joan McMahon, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, Joan McMahon, MD's most frequently prescribed drugs include Lisinopril, Atorvastatin Calcium, Albuterol Sulfate Hfa. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Joan McMahon, MD accept Medicare? ▼
Joan McMahon, MD appears in CMS Medicare data with 443 Part D claims and 90 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Joan McMahon, MD's credentials? ▼
Joan McMahon, MD's NPI is 1467403345 with credentials MD. 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.