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Optometry

Margaret J. Slowik, OD

Sees patients in La Grange, IL · Downers Grove, IL · Illinois

Summary

Dr. Margaret J. Slowik, OD is an optometrist at 100 W Calendar Ave, La Grange, IL 60525. Phone: (708) 354-0500. Accepts Medicare assignment. In 2024, Margaret J. Slowik had 62 Original Medicare patients and 68 services. NPI 1124222591. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Optometrist (Medicare lists Optometry)
  • Address: 100 W Calendar Ave, La Grange, IL 60525 · Directions (1 more location)
  • Phone: (708) 354‑0500
  • Medicare: Accepts Medicare assignment
  • Group practice: Rosin Optical Co Inc
  • Optometry school: Illinois College Of Optometry At Chicago · graduated 1994 (32 years since optometry school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Margaret J. Slowik, 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 Margaret J. Slowik accept Medicare assignment?
Yes. Medicare's clinician data says Margaret J. Slowik 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 Margaret J. Slowik see?
In 2024, CMS data shows 62 Original Medicare patients and 68 services for Margaret J. Slowik. This counts Original Medicare only and measures volume, not quality.
What is Margaret J. Slowik's NPI number?
1124222591. 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 Margaret J. Slowik, 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 patients62
Services billed to Medicare68
Different services or procedures6
Participating Medicare providerYes
Average age of these patients74

Most frequent services

  1. Established patient complete exam of visual system (92014)47 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 pressure63%
  • Arthritis47%
  • Ischemic heart disease32%
  • Osteoporosis21%
  • Atrial fibrillation18%

Practice locations

Addresses where Margaret J. Slowik is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Margaret J. Slowik as a member of this group (CMS data updated October 2, 2026).

  • Rosin Optical Co Inc51 clinicians in the group

Specialties

Find other clinicians: Optometry, Illinois →

Other optometrists in La Grange

Clinicians with the same Medicare primary specialty in La Grange, IL — not a recommendation.

All optometrists in La Grange →

Other clinicians in Rosin Optical Co Inc

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

Clinician information

CredentialOD
Optometry schoolIllinois College Of Optometry At Chicago
Graduation year1994 (32 years since optometry school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1124222591
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