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Emergency Medicine

Jennie G. Walker, MD

Works at hospitals in Mammoth Lakes, CA · California

Summary

Dr. Jennie G. Walker, MD is an emergency medicine doctor at 85 Sierra Park Rd, Mammoth Lakes, CA 93546. Phone: (760) 934-3311. Accepts Medicare assignment. In 2024, Jennie G. Walker had 16 Original Medicare patients and 25 services. NPI 1558371229. 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: 85 Sierra Park Rd, Mammoth Lakes, CA 93546 · Directions
  • Phone: (760) 934‑3311
  • Medicare: Accepts Medicare assignment
  • Hospital: Mammoth Hospital
  • Group practice: Southern Mono Health Care District
  • Medical school: R Franklin University Of Med & Sci/chicago Medical School · graduated 1999 (27 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Jennie G. Walker, 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 Jennie G. Walker accept Medicare assignment?
Yes. Medicare's clinician data says Jennie G. Walker 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 Jennie G. Walker see?
In 2024, CMS data shows 16 Original Medicare patients and 25 services for Jennie G. Walker. This counts Original Medicare only and measures volume, not quality.
What is Jennie G. Walker's NPI number?
1558371229. 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 Jennie G. Walker, 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 patients16
Services billed to Medicare25
Different services or procedures5
Participating Medicare providerYes
Average age of these patients76

Most frequent services

  1. Emergency department visit with high level of medical decision making (99285)13 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%

Hospitals where Jennie G. Walker works

Medicare's Facility Affiliation Data lists Jennie G. Walker 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.

  • Mammoth HospitalMammoth Lakes, CA · Critical Access Hospital · Emergency services: listed by Medicare · CCN 051303

Practice locations

Addresses where Jennie G. Walker is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Jennie G. Walker as a member of this group (CMS data updated October 2, 2026).

  • Southern Mono Health Care District100 clinicians in the group

Specialties

Find other Emergency Medicine doctors in California →

Other emergency medicine doctors in Mammoth Lakes

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

All emergency medicine doctors in Mammoth Lakes →

Other clinicians in Southern Mono Health Care District

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

Clinician information

CredentialMD
Medical schoolR Franklin University Of Med & Sci/chicago Medical School
Graduation year1999 (27 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1558371229
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