Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
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Dr. Olivia Maslon Siwoski, MD

Individual provider Internal Medicine Physician · NPI 1609260884

Dr. Olivia Maslon Siwoski, MD practises Internal Medicine in Kalamazoo, Michigan. Qualified in 2015, 11 years ago. Practices with Bronson Methodist Hospital, a 719-clinician group, works from 2 locations and accepts Medicare assignment. Licensed in Michigan.

Years since qualifying
11
Licensed in
MI
In the registry since
2015
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

601 John St
Kalamazoo, MI 49007-5341
Phone: (269) 341-8481
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 965 S Bailey Ave Ste 101, South Haven, MI 49090-6743 — (269) 639-2777

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence 4301503659 (MI)

Record details

NPI number1609260884
Entity typeIndividual (Type 1)
GenderFemale
Credentials MD
Sole proprietorNo
NPI enumeratedMarch 25, 2015
Last updated in NPPESDecember 7, 2021
Certification dateDecember 7, 2021

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyINTERNAL MEDICINE
Also practisesHOSPITALIST
Medical schoolOTHER
Graduated 2015 (11 years in practice)
Group practice Bronson Methodist Hospital — 719 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients203
Services billed 405 a service is one billed item, such as a visit, a test or a procedure
Average patient age76

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $123 4 payments · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at Bronson Methodist Hospital

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 719 clinicians in the practice; 12 are shown here.

Other providers in Kalamazoo