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Emergency Medicine

Katherine V. Bayer, MD

Works at hospitals in Lake Forest, IL · Winfield, IL · Chicago, IL · Illinois

Summary

Dr. Katherine V. Bayer, MD is an emergency medicine doctor at 6155 Grand Ave, Suite 100, Gurnee, IL 60031. Phone: (224) 271-6700. Accepts Medicare assignment. In 2024, Katherine V. Bayer had 385 Original Medicare patients and 3,017 services. NPI 1548587504. 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.

From official Medicare data

This page shows what Medicare's official clinician data says about Katherine V. Bayer, 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 Katherine V. Bayer accept Medicare assignment?
Yes. Medicare's clinician data says Katherine V. Bayer 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 Katherine V. Bayer see?
In 2024, CMS data shows 385 Original Medicare patients and 3,017 services for Katherine V. Bayer. This counts Original Medicare only and measures volume, not quality.
What is Katherine V. Bayer's NPI number?
1548587504. 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 Katherine V. Bayer, 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 patients385
Services billed to Medicare3,017
Different services or procedures80
Participating Medicare providerYes
Average age of these patients75

Most frequent services

  1. Low osmolar contrast material, 300-399 mg/ml iodine concentration, per ml (Q9967)1,374 services
  2. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)82 services
  3. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)74 services
  4. Insertion of needle into vein for collection of blood sample (36415)52 services
  5. X-ray of chest, 2 views (71046)45 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 cholesterol75%
  • High blood pressure67%
  • Arthritis57%
  • Ischemic heart disease29%
  • Anxiety29%
  • Osteoporosis24%

Hospitals where Katherine V. Bayer works

Medicare's Facility Affiliation Data lists Katherine V. Bayer 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 Katherine V. Bayer is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Katherine V. Bayer as a member of this group (CMS data updated October 2, 2026).

  • Northwestern Medical Faculty Foundation4,503 clinicians in the group

Specialties

Find other Emergency Medicine doctors in Illinois →

Other emergency medicine doctors in Illinois

Clinicians with the same Medicare primary specialty in Illinois — not a recommendation.

All emergency medicine doctors in Illinois →

Other clinicians in Northwestern Medical Faculty Foundation

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

Clinician information

CredentialMD
Medical schoolRush Medical College Of Rush University
Graduation year2010 (16 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1548587504
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