Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Dr. Mark W Day, DO

Individual provider Obstetrics & Gynecology Physician · NPI 1225050560

Dr. Mark W Day, DO practises Obstetrics/Gynecology in Middletown, Ohio. Graduated from Des Moines University of Osteopathic Medicine and Health Sciences in 1995, 31 years ago. Practices with Dayton Osteopathic Hospital, a 35-clinician group and accepts Medicare assignment. Licensed in Ohio.

Years since qualifying
31
Trained at
Des Moines University of Osteopathic Medicine and Health Sciences
Licensed in
OH
In the registry since
2006
Specialties on file
2
What do these letters mean?
DO — Doctor of Osteopathic Medicine
A fully licensed physician, trained like an MD with additional musculoskeletal training. Equivalent practice rights in all 50 states.

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Practice location Address checks out

6147 State Route 122 Ste 110
Middletown, OH 45005-5201
Phone: (513) 261-3500
Fax: (513) 261-3509
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Obstetrics & Gynecology Physician (primary) Taxonomy 207V00000X · Licence 34.007014 (OH)
Obstetrics & Gynecology Physician Taxonomy 207V00000X · Licence 31-1715747 (OH)

Record details

NPI number1225050560
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorYes
NPI enumeratedJuly 24, 2006
Last updated in NPPESFebruary 1, 2021
Certification dateFebruary 1, 2021

Medicare enrollment

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

Medicare specialtyOBSTETRICS/GYNECOLOGY
Medical schoolDES MOINES UNIVERSITY OF OSTEOPATHIC MEDICINE AND HEALTH SCIENCES
Graduated 1995 (31 years in practice)
Group practice Dayton Osteopathic Hospital — 35 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations5 on file with Medicare

Procedures

From CMS Care Compare, which counts the procedures a clinician billed to Original Medicare and Medicare Advantage over a recent 12-month period. CMS reports a fixed list of common procedures, so this is not everything the clinician does. Counts of 10 or fewer are given as a range, because CMS withholds small numbers.

Removal of the uterus 1–10 times

The percentile compares how often this clinician performed the procedure with other clinicians who performed it, as CMS calculates it. It measures volume, not outcomes or skill.

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 patients23
Services billed 344 a service is one billed item, such as a visit, a test or a procedure
Average patient age65

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 $29 1 payment · 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. Those with a page here are linked.

  • Kettering Health Main Campus Hospital · Kettering, OH · listed as Kettering Medical Center
  • Kettering Health Dayton Hospital · Dayton, OH

Colleagues at Dayton Osteopathic Hospital

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 35 clinicians in the practice; 12 are shown here.

Other providers in Middletown