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Emergency Medicine

Jennifer L. Mason, MD

Works at hospitals in Anaheim, CA · California

Summary

Dr. Jennifer L. Mason, MD is an emergency medicine doctor at 3033 W Orange Ave, Anaheim, CA 92804. Phone: (714) 827-3000. Accepts Medicare assignment. In 2024, Jennifer L. Mason had 291 Original Medicare patients and 329 services. NPI 1396828216. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Emergency medicine doctor (Medicare lists Emergency Medicine)
  • Address: 3033 W Orange Ave, Anaheim, CA 92804 · Directions
  • Phone: (714) 827‑3000
  • Medicare: Accepts Medicare assignment
  • Hospital: West Anaheim Medical Center
  • Group practice: South Coast Emergency Medical Group
  • Medical school: University Of Southern California Keck School Of Medicine · graduated 1993 (33 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Jennifer L. Mason, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Jennifer L. Mason accept Medicare assignment?
Yes. Medicare's clinician data says Jennifer L. Mason accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Jennifer L. Mason see?
In 2024, CMS data shows 291 Original Medicare patients and 329 services for Jennifer L. Mason. This counts Original Medicare only and measures volume, not quality.
What is Jennifer L. Mason's NPI number?
1396828216. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Jennifer L. Mason, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients291
Services billed to Medicare329
Different services or procedures11
Participating Medicare providerYes
Average age of these patients74

Most frequent services

  1. Emergency department visit with high level of medical decision making (99285)145 services
  2. Critical care, first 30-74 minutes (99291)131 services
  3. Emergency department visit with moderate level of medical decision making (99284)33 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure75%
  • High cholesterol75%
  • Arthritis61%
  • Diabetes60%
  • Depression58%
  • Chronic kidney disease49%

Hospitals where Jennifer L. Mason works

Medicare's Facility Affiliation Data lists Jennifer L. Mason at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

Practice locations

Addresses where Jennifer L. Mason is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Jennifer L. Mason as a member of this group (CMS data updated October 2, 2026).

  • South Coast Emergency Medical Group9 clinicians in the group

Specialties

Find other Emergency Medicine doctors in California →

Other emergency medicine doctors in Anaheim

Clinicians with the same Medicare primary specialty in Anaheim, CA — not a recommendation.

All emergency medicine doctors in Anaheim →

Other clinicians in South Coast Emergency Medical Group

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialMD
Medical schoolUniversity Of Southern California Keck School Of Medicine
Graduation year1993 (33 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1396828216
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians