2026 NPPES data Family Medicine Physician NPI 1891834891 MD
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REX BAKER, MD

Family Medicine Physician in SALEM, Oregon. 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
302
Medicare Part D claims · 220 beneficiaries · Family Medicine Physician avg: 3K
Generic prescribing
90%
generic claims · 10% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

REX BAKER, MD filed 302 Medicare Part D claims in 2023 as a Family Medicine Physician in SALEM, Oregon, prescribing 90% generic.

302
Part D claims, 2023
90%
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.

REX BAKER, MD's Medicare Part D volume vs every U.S. prescriber

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

302 Top 43% higher than 57% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). This entry sits in this band. 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)

REX BAKER, 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 REX BAKER, MD?

Quality data not reported

NPI registry status

Active

Issued 02/06/2007

NPI 1891834891

Primary specialty

Family Medicine Physician

High-volume

147,640 US NPIs in this specialty

Medicare Part D claims

302 91% vs specialty avg

2023 prescription claims

Specialty avg: 3,418

Specialty distribution in Oregon

How Family Medicine Physician compares to other specialties among Oregon providers

Oregon providers

Family Medicine Physician share within Oregon

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

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).

REX BAKER, MD appears in the CMS NPPES registry as a Family Medicine Physician provider holding MD credentials at 2400 LANCASTER DR NE, SALEM, OR, 97305, with a listed phone of (503) 361-5400. NPI 1891834891 was issued on 02/06/2007. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what BAKER 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 302 prescription claims written by this provider, covering 220 Medicare beneficiaries and totaling roughly $8K in drug spend, split 10% brand-name and 90% generic by claim count, with an opioid prescribing rate of 7.6%. 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

2400 LANCASTER DR NE
SALEM, OR 97305

Provider Details

NPI 1891834891
Specialty Family Medicine Physician
Credentials MD
Gender Male
NPI Issued 02/06/2007

Hospital and facility affiliations

Facilities where REX BAKER, 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.

KAISER FOUNDATION HEALTH PLAN OF THE NORTHWEST
CLACKAMAS, OR

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

REX BAKER, MD — brand share 10.0%
Specialty average (est.)

10% brand-name claims vs 90% generic, on 302 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.

302
Total Claims
$8K
Total Drug Cost
220
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
374
Total Day Supply
6,488
Brand vs Generic
10% brand / 90% generic
Brand Drug Cost
$3K
Generic Drug Cost
$5K
Opioid Claims
23 (7.6% rate)
Antibiotic Claims
101

Patient Demographics

Average Patient Age
73.6 years
Avg HCC Risk Score
1.27
Gender Split
60% female / 40% male
Age Distribution
<65: 21, 65-74: 107, 75-84: 66, 85+: 26

Top Prescribed Drugs (Medicare Part D)

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

What REX BAKER, MD prescribes most

Top Medicare Part D drugs by claim count, 2023

claims
Source CMS Medicare Part D Prescriber Public Use File As of 2023
Drug Claims
Doxycycline Monohydrate
24
Prednisone
18
Albuterol Sulfate Hfa
Albuterol Sulfate
17
Cefadroxil
15
Hydrocodone-Acetaminophen
Hydrocodone/Acetaminophen
14
Nitrofurantoin Mono-Macro
Nitrofurantoin Monohyd/M-Cryst
14
Amoxicillin
12
Paxlovid (Eua)
Nirmatrelvir/Ritonavir
11

* 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 REX BAKER, 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

REX BAKER, MD's 302 claims are below the specialty average of 3,418.

Nearby Family Medicine Physician Providers in Oregon

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

Compare Family Medicine Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is REX BAKER, MD's specialty?
REX BAKER, MD specializes in Family Medicine Physician and practices in SALEM, Oregon. Credentials: MD.
How much does REX BAKER, MD prescribe under Medicare Part D?
In 2023, REX BAKER, MD wrote 302 Medicare Part D claims totaling $8K in drug costs for 220 beneficiaries.
Where is REX BAKER, MD located?
REX BAKER, MD is located at 2400 LANCASTER DR NE, SALEM, OR, 97305. Phone: (503) 361-5400.
What is REX BAKER, MD's NPI number?
REX BAKER, MD's National Provider Identifier (NPI) is 1891834891, issued on 02/06/2007.
Does REX BAKER, MD prescribe more brand-name or generic drugs?
REX BAKER, MD's prescribing is 10% brand-name and 90% generic drugs by claim count, with $3K in brand drug costs.
Does REX BAKER, MD prescribe opioids?
Yes, REX BAKER, MD had 23 opioid claims in 2023 with an opioid prescribing rate of 7.6%.
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 REX BAKER, MD prescribe most often?
Based on 2023 Medicare Part D data, REX BAKER, MD's most frequently prescribed drugs include Doxycycline Monohydrate, Prednisone, Albuterol Sulfate Hfa. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does REX BAKER, MD accept Medicare?
REX BAKER, MD appears in CMS Medicare data with 302 Part D claims and 220 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify REX BAKER, MD's credentials?
REX BAKER, MD's NPI is 1891834891 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