2026 NPPES data Family Medicine Physician NPI 1538112883 MD
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Marta Mortensen, MD

Family Medicine Physician in Saint Louis, Missouri. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
Prescribing volume
108
Medicare Part D claims · 37 beneficiaries · Family Medicine Physician avg: 3K
Generic prescribing
88%
generic claims · 12% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

Marta Mortensen, MD filed 108 Medicare Part D claims in 2023 as a Family Medicine Physician in Saint Louis, Missouri, prescribing 88% generic.

108
Part D claims, 2023
88%
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.

Marta Mortensen, MD's Medicare Part D volume vs every U.S. prescriber

Total Medicare Part D claims, 2023 — across all CMS prescribers nationally

108 35th percentile higher than 35% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). This entry sits in this band. 200–400: 182,923 prescribers (13%). Above this entry. 400–600: 90,619 prescribers (7%). Above this entry. 600–800: 56,224 prescribers (4%). Above this entry. 800–1,000: 40,919 prescribers (3%). Above this entry. 1,000–1,200: 31,827 prescribers (2%). Above this entry. 1,200–1,400: 26,224 prescribers (2%). Above this entry. 1,400–1,600: 21,710 prescribers (2%). Above this entry. 1,600–1,800: 19,072 prescribers (1%). Above this entry. 1,800–2,000: 16,451 prescribers (1%). Above this entry. 2,000–2,200: 213,991 prescribers (16%). Above this entry. This provider 0 2K+ every Part D prescriber (claims/yr), bucketed by value

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)

Marta Mortensen, 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 Marta Mortensen, MD?

Quality data not reported

NPI registry status

Active

Issued 05/18/2006

NPI 1538112883

Primary specialty

Family Medicine Physician

High-volume

147,640 US NPIs in this specialty

Medicare Part D claims

108 97% vs specialty avg

2023 prescription claims

Specialty avg: 3,418

Specialty distribution in Missouri

How Family Medicine Physician compares to other specialties among Missouri providers

Missouri providers

Family Medicine Physician share within Missouri

1. Family Medicine Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Family Medicine Physician share within Missouri

Specialty board-certification context

Estimated specialty board-certified rate — Family Medicine Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Family Medicine Physician ABMS/AOA estimate

Est. board-certified rate (Family Medicine Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Family Medicine Physician) — ABMS / AOA estimate

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).

Marta Mortensen, MD appears in the CMS NPPES registry as a Family Medicine Physician provider holding MD credentials at 8793 WATSON RD, Saint Louis, MO, 63119, with a listed phone of (314) 961-0900. NPI 1538112883 was issued on 05/18/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what Mortensen most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 108 prescription claims written by this provider, covering 37 Medicare beneficiaries and totaling roughly $3K in drug spend, split 12% brand-name and 88% generic by claim count. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Family Medicine Physician is a high-volume specialty nationwide, with 147,640 enrolled providers across 56 states and an average of 3,418 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

8793 WATSON RD
Saint Louis, MO 63119

Provider Details

NPI 1538112883
Specialty Family Medicine Physician
Credentials MD
Gender Female
NPI Issued 05/18/2006

Hospital and facility affiliations

Facilities where Marta Mortensen, 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.

Missouri State University
Springfield, MO

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

Brand vs generic prescribing mix · Typical

Marta Mortensen, MD — brand share 12.0%
Specialty average (est.)

12% brand-name claims vs 88% generic, on 108 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.

108
Total Claims
$3K
Total Drug Cost
37
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
198
Total Day Supply
5,440
Brand vs Generic
12% brand / 88% generic
Brand Drug Cost
$2K
Generic Drug Cost
$1K
Antibiotic Claims
12

Patient Demographics

Average Patient Age
73.1 years
Avg HCC Risk Score
0.90
Gender Split
51% female / 49% male

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

Drug Claims
Amlodipine Besylate
13

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

Family Medicine Physician Overview

How Marta Mortensen, MD fits within the Family Medicine Physician landscape nationally.

147,640
Family Medicine Physician Providers in US
56
States with Family Medicine Physician
3,418
Avg Claims per Provider

Marta Mortensen, MD's 108 claims are below the specialty average of 3,418.

Nearby Family Medicine Physician Providers in Missouri

Other clinicians with the same primary specialty enrolled in Missouri, drawn from the same CMS NPPES roster as Mortensen.

Compare Family 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 Missouri medical board — federal registration is not a license check. Credential verification guide
  • Weigh a second option: compare this provider with a nearby Family 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.

Frequently Asked Questions

What is Marta Mortensen, MD's specialty?
Marta Mortensen, MD specializes in Family Medicine Physician and practices in Saint Louis, Missouri. Credentials: MD.
How much does Marta Mortensen, MD prescribe under Medicare Part D?
In 2023, Marta Mortensen, MD wrote 108 Medicare Part D claims totaling $3K in drug costs for 37 beneficiaries.
Where is Marta Mortensen, MD located?
Marta Mortensen, MD is located at 8793 WATSON RD, Saint Louis, MO, 63119. Phone: (314) 961-0900.
What is Marta Mortensen, MD's NPI number?
Marta Mortensen, MD's National Provider Identifier (NPI) is 1538112883, issued on 05/18/2006.
Does Marta Mortensen, MD prescribe more brand-name or generic drugs?
Marta Mortensen, MD's prescribing is 12% brand-name and 88% generic drugs by claim count, with $2K in brand drug costs.
How many Family Medicine Physician providers are there in the US?
There are 147,640 Family Medicine Physician providers across 56 states in the US. The average Family Medicine Physician provider writes 3,418 Medicare Part D claims per year.
What drugs does Marta Mortensen, MD prescribe most often?
Based on 2023 Medicare Part D data, Marta Mortensen, MD's most frequently prescribed drugs include Amlodipine Besylate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Marta Mortensen, MD accept Medicare?
Marta Mortensen, MD appears in CMS Medicare data with 108 Part D claims and 37 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Marta Mortensen, MD's credentials?
Marta Mortensen, MD's NPI is 1538112883 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

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