NPI registry status
Active
2026 NPPES data Emergency Medicine Physician NPI 1164841383 M.D.
Verify on CMS → Joshua Westeren, M.D.
Emergency Medicine Physician in Loma Linda, California.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 64,463 in Emergency 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
246
Medicare Part D claims · 156 beneficiaries · Emergency Medicine Physician avg: 352
What the federal data shows
Joshua Westeren, M.D. filed 246 Medicare Part D claims in 2023 as an Emergency Medicine Physician in Loma Linda, California.
- 246
- Part D claims, 2023
- Likely
- board-certified (heuristic)
- ≥49th
- pct by Part D claim volume (lower-bound band)
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.
Federal trust snapshot
What official records show about Joshua Westeren, M.D.
Federal records show an active NPI with Medicare Part D prescribing activity — verifiable registry data, not a proprietary rating.
- Verified
NPI registry status
Active listing in the CMS National Provider Identifier Registry (NPI 1164841383), first enumerated 04/15/2014.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 246 Medicare Part D prescription claims in the 2023 CMS public use file — indicates active Medicare prescribing participation.
Source: CMS Part D Prescriber PUF
- Reported
Board certification signal
Heuristic suggests board-certified status based on ABMS-eligible specialty taxonomy plus active CMS participation signals — not a direct ABMS verification.
- Reported
Hospital affiliations
1 CMS Care Compare hospital affiliation on record — practice footprint from the Doctors and Clinicians file.
Source: CMS Care Compare
- State context
State board disciplinary context
California statewide board action statistics are published annually — these figures describe aggregate state activity, not Joshua Westeren, M.D.'s individual license status. Verify directly with the state medical board.
Source: MBC annual report 2023
- Not in federal data
Individual sanction lookup
PlainDoctor does not publish per-provider disciplinary determinations. Confirm current license and any individual actions through the state medical board or FSMB verification service.
Source: State medical board / FSMB
This trust snapshot summarizes only what appears in federal CMS/NPPES public records. It is not a composite score, star rating, patient review, or clinical recommendation. PlainDoctor never fabricates reviews or AggregateRating schema.
CMS NPPES provider registry desk
NPI 1164841383 · Emergency Medicine Physician
NPI-10 · ENUM-MID · TAX-MEGA · RX-LIGHT · BOOK-MID · PHOTO-ENUM
- NPI-10 1164841383
- ENUM-MID 2014
- TAX-MEGA 64K Emergency Medicine
- RX-LIGHT 246
- BOOK-MID 6,965 in California
- PHOTO-ENUM Eric Golike · 2014
Joshua Westeren, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
246 ≥ 49th percentile 49% of 1,370,886 prescribers are in lower value bands
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.
The percentile is a conservative 100-claim band: it counts only prescribers in lower claim-volume bands. Medicare Part D claim volume is activity context, not a quality measure or recommendation. See methodology § corpus placement.
Source CMS Medicare Part D Prescriber Public Use File · 2023
✓
Board certification likely (heuristic, not verified)
Joshua Westeren, M.D. 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 Joshua Westeren, M.D.?
Quality data not reportedPrimary specialty
Emergency Medicine Physician
Medicare Part D claims
246 30% vs specialty avg
Specialty distribution in California
How Emergency Medicine Physician compares to other specialties among California 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 Emergency Medicine 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).
Practice Address
Provider Details
| NPI | 1164841383 |
|---|---|
| Specialty | Emergency Medicine Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 04/15/2014 |
Hospital and facility affiliations
Facilities where Joshua Westeren, M.D. 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.
Tacoma Emergency Care Physicians PLLC
Covington, WA
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
License & disciplinary context - California MBC 2023 annual report
Aggregate state board data only, NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~150K California medical licensees in 2023 - they are NOT specific to Joshua Westeren, M.D.. To verify Joshua Westeren, M.D.'s current license status, search the MBC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
576
Total board actions, California 2023
Across 556 cases
3.84
Actions per 1,000 licensees
California statewide rate
probation
Most common action type
186 cases
MBC publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the California disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2023.
246
Total Claims
$6K
Total Drug Cost
156
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 248
- Total Day Supply
- 2,450
- Generic Drug Cost
- $3K
- Opioid Claims
- 21 (8.5% rate)
- Antibiotic Claims
- 81
Patient Demographics
- Average Patient Age
- 70.6 years
- Avg HCC Risk Score
- 1.44
- Gender Split
- 65% female / 35% male
- Age Distribution
- <65: 33, 65-74: 55, 75-84: 45, 85+: 23
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Joshua Westeren, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2023
- Cephalexin
Cephalexin
31 claims
- Prednisone
Prednisone
29 claims
- Ondansetron Odt
Ondansetron Odt
22 claims
- Hydrocodone-Acetam…
Hydrocodone-Acetaminophen
19 claims
- Doxycycline Hyclate
Doxycycline Hyclate
16 claims
| Drug | Claims |
|---|---|
| Cephalexin | 31 |
| Prednisone | 29 |
| Ondansetron Odt Ondansetron | 22 |
| Hydrocodone-Acetaminophen Hydrocodone/Acetaminophen | 19 |
| Doxycycline Hyclate | 16 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Emergency Medicine Physician Overview
How Joshua Westeren, M.D. fits within the Emergency Medicine Physician landscape nationally.
64,463
Emergency Medicine Physician Providers in US
56
States with Emergency Medicine Physician
352
Avg Claims per Provider
Joshua Westeren, M.D.'s 246 claims are below the specialty average of 352.
Nationwide Emergency Medicine Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Westeren, both outside California so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2014)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Emergency Medicine Physician Providers in California
Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as Westeren.
One of 6,965 Emergency Medicine Physician providers enrolled in California, 5 are shown here.
Dr. Cooper Aakhus
MD
Stanford, CA
Dr. Pyra Aarden
MD
Martinez, CA
Dr. Neal Aaron
D.O.
Encinitas, CA
Eric Aaserude
Walnut Creek, CA
Dr. Nader Abas
MD
Barstow, CA
Compare Emergency Medicine Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is Joshua Westeren, M.D.'s specialty? ▼
Joshua Westeren, M.D. specializes in Emergency Medicine Physician and practices in Loma Linda, California. Credentials: M.D..
How much does Joshua Westeren, M.D. prescribe under Medicare Part D? ▼
In 2023, Joshua Westeren, M.D. wrote 246 Medicare Part D claims totaling $6K in drug costs for 156 beneficiaries.
Where is Joshua Westeren, M.D. located? ▼
Joshua Westeren, M.D. is located at 11234 ANDERSON ST, Loma Linda, CA, 92354. Phone: (909) 558-4085.
What is Joshua Westeren, M.D.'s NPI number? ▼
Joshua Westeren, M.D.'s National Provider Identifier (NPI) is 1164841383, issued on 04/15/2014.
Does Joshua Westeren, M.D. prescribe opioids? ▼
Yes, Joshua Westeren, M.D. had 21 opioid claims in 2023 with an opioid prescribing rate of 8.5%.
How many Emergency Medicine Physician providers are there in the US? ▼
There are 64,463 Emergency Medicine Physician providers across 56 states in the US. The average Emergency Medicine Physician provider writes 352 Medicare Part D claims per year.
What drugs does Joshua Westeren, M.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, Joshua Westeren, M.D.'s most frequently prescribed drugs include Cephalexin, Prednisone, Ondansetron Odt. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Joshua Westeren, M.D. accept Medicare? ▼
Joshua Westeren, M.D. appears in CMS Medicare data with 246 Part D claims and 156 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Joshua Westeren, M.D.'s credentials? ▼
Joshua Westeren, M.D.'s NPI is 1164841383 with credentials M.D.. 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.