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Emergency Medicine

Lynn L. Ji, MD

Sees patients in San Diego, CA · La Mesa, CA · California

Summary

Dr. Lynn L. Ji, MD is an emergency medicine doctor at 4647 Zion Ave, San Diego, CA 92120. Phone: (619) 528-5000. Accepts Medicare assignment. In 2024, Lynn L. Ji had 17 Original Medicare patients and 30 services. NPI 1346442308. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Emergency medicine doctor (Medicare lists Emergency Medicine)
  • Address: 4647 Zion Ave, San Diego, CA 92120 · Directions (1 more location)
  • Phone: (619) 528‑5000
  • Medicare: Accepts Medicare assignment
  • Group practice: Southern California Permanente Medical Group
  • Medical school: graduated 2005 (21 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Lynn L. Ji, 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 Lynn L. Ji accept Medicare assignment?
Yes. Medicare's clinician data says Lynn L. Ji 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 Lynn L. Ji see?
In 2024, CMS data shows 17 Original Medicare patients and 30 services for Lynn L. Ji. This counts Original Medicare only and measures volume, not quality.
What is Lynn L. Ji's NPI number?
1346442308. 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 Lynn L. Ji, 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 patients17
Services billed to Medicare30
Different services or procedures10
Participating Medicare providerYes
Average age of these patients69

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 cholesterol71%

Practice locations

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

Group practices

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

  • Southern California Permanente Medical Group11,293 clinicians in the group

Specialties

Find other Emergency Medicine doctors in California →

Other emergency medicine doctors in San Diego

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

All emergency medicine doctors in San Diego →

Other clinicians in Southern California Permanente Medical Group

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

Clinician information

CredentialMD
Graduation year2005 (21 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1346442308
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. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  2. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians