NPI registry status
Active
2026 NPPES data Hospitalist Physician NPI 1396972279 MD
Verify on CMS → Mark Nelson, MD
Hospitalist Physician in Denver, Colorado.
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
1K
Medicare Part D claims · 102 beneficiaries · Hospitalist Physician avg: 888
Generic prescribing
87%
generic claims · 12% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2023
What the federal data shows
Mark Nelson, MD filed 1,376 Medicare Part D claims in 2023 as a Hospitalist Physician in Denver, Colorado, prescribing 87% generic.
- 1K
- Part D claims, 2023
- 87%
- generic prescribing
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.
Mark Nelson, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
1,376 Top 21% higher than 79% 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-eligible specialty (heuristic, not verified)
Mark Nelson, MD practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about Mark Nelson, MD?
Quality data not reportedPrimary specialty
Hospitalist Physician
Medicare Part D claims
1,376 55% vs specialty avg
Specialty distribution in Colorado
How Hospitalist Physician compares to other specialties among Colorado 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).
Mark Nelson, MD appears in the CMS NPPES registry as a Hospitalist Physician provider holding MD credentials at 1960 N OGDEN ST STE 120, Denver, CO, 80218, with a listed phone of (303) 318-3840. NPI 1396972279 was issued on 06/17/2009.
Medicare Part D records for calendar year 2023 show 1,376 prescription claims written by this provider, covering 102 Medicare beneficiaries and totaling roughly $156K in drug spend, split 12% brand-name and 87% generic by claim count.
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 | 1396972279 |
|---|---|
| Specialty | Hospitalist Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 06/17/2009 |
Brand vs generic prescribing mix · Typical
Mark Nelson, MD - brand share 12.0%
Hospitalist Physician average
12% brand-name claims vs 87% generic, on 1,376 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.
1,376
Total Claims
$156K
Total Drug Cost
102
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 3,340
- Total Day Supply
- 96,493
- Brand vs Generic
- 12% brand / 87% generic
- Brand Drug Cost
- $126K
- Generic Drug Cost
- $30K
- Antibiotic Claims
- 72
Patient Demographics
- Average Patient Age
- 75.9 years
- Avg HCC Risk Score
- 0.97
- Gender Split
- 43% female / 57% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Mark Nelson, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Atorvastatin Calcium
Atorvastatin Calcium
101 claims
- Amlodipine Besylate
Amlodipine Besylate
89 claims
- Levothyroxine Sodium
Levothyroxine Sodium
65 claims
- Rosuvastatin Calcium
Rosuvastatin Calcium
44 claims
- Hydrochlorothiazide
Hydrochlorothiazide
43 claims
- Lisinopril 40
Lisinopril
40 claims
- Zolpidem Tartrate 40
Zolpidem Tartrate
40 claims
- Alprazolam 28
Alprazolam
28 claims
| Drug | Claims |
|---|---|
| Atorvastatin Calcium | 101 |
| Amlodipine Besylate | 89 |
| Levothyroxine Sodium | 65 |
| Rosuvastatin Calcium | 44 |
| Hydrochlorothiazide | 43 |
| Lisinopril | 40 |
| Zolpidem Tartrate | 40 |
| Alprazolam | 28 |
| Amoxicillin-Clavulanate Potass Amoxicillin/Potassium Clav | 28 |
| Xarelto Rivaroxaban | 26 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Hospitalist Physician Overview
How Mark Nelson, 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
Mark Nelson, MD's 1,376 claims are above the specialty average of 888.
Nearby Hospitalist Physician Providers in Colorado
Other clinicians with the same primary specialty enrolled in Colorado, drawn from the same CMS NPPES roster as Nelson.
Dr. Sahar Abdelqader
MD
Longmont, CO
Aida Abraham
Castle Rock, CO
Dr. Guy Adair
DO, MBS
Aurora, CO
Dr. Katlynn Adkins
MD
Denver, CO
Dr. Brian Agganis
M.D.
Aurora, CO
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 Colorado 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.
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Frequently Asked Questions
What is Mark Nelson, MD's specialty? ▼
Mark Nelson, MD specializes in Hospitalist Physician and practices in Denver, Colorado. Credentials: MD.
How much does Mark Nelson, MD prescribe under Medicare Part D? ▼
In 2023, Mark Nelson, MD wrote 1,376 Medicare Part D claims totaling $156K in drug costs for 102 beneficiaries.
Where is Mark Nelson, MD located? ▼
Mark Nelson, MD is located at 1960 N OGDEN ST STE 120, Denver, CO, 80218. Phone: (303) 318-3840.
What is Mark Nelson, MD's NPI number? ▼
Mark Nelson, MD's National Provider Identifier (NPI) is 1396972279, issued on 06/17/2009.
Does Mark Nelson, MD prescribe more brand-name or generic drugs? ▼
Mark Nelson, MD's prescribing is 12% brand-name and 87% generic drugs by claim count, with $126K in brand drug costs.
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 Mark Nelson, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, Mark Nelson, MD's most frequently prescribed drugs include Atorvastatin Calcium, Amlodipine Besylate, Levothyroxine Sodium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Mark Nelson, MD accept Medicare? ▼
Mark Nelson, MD appears in CMS Medicare data with 1,376 Part D claims and 102 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Mark Nelson, MD's credentials? ▼
Mark Nelson, MD's NPI is 1396972279 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
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.