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

Thomas Kobina Duncan, DO

Individual provider Surgery Physician · NPI 1316097439

Thomas Kobina Duncan, DO practises General Surgery in Ventura, California. Graduated from Midwestern University, Chicago College of Osteopathic Med in 1992, 34 years ago. Practices with Ventura County Surgical Associates, an 11-clinician group and accepts Medicare assignment. Licensed in California.

Years since qualifying
34
Trained at
Midwestern University, Chicago College of Osteopathic Med
Licensed in
CA
In the registry since
2007
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

300 Hillmont Ave Ste 401
Ventura, CA 93003-1651
Phone: (805) 652-6201
Fax: (805) 641-4416
Show map & directions

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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Surgery Physician (primary) Taxonomy 208600000X · Licence 20A6490 (CA)

Record details

NPI number1316097439
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorNo
NPI enumeratedJanuary 11, 2007
Last updated in NPPESMay 20, 2026
Certification dateMay 20, 2026

Medicare enrollment

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

Medicare specialtyGENERAL SURGERY
Medical schoolMIDWESTERN UNIVERSITY, CHICAGO COLLEGE OF OSTEOPATHIC MED
Graduated 1992 (34 years in practice)
Group practice Ventura County Surgical Associates — 11 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations2 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.

Hernia repair (minimally invasive) 1–10 times
Hernia repair - groin (open) 1–10 times
Mastectomy 1–10 times
Upper gastrointestinal (GI) endoscopy for acid reflux 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 patients64
Services billed 120 a service is one billed item, such as a visit, a test or a procedure
Average patient age74

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 $152 2 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 Ventura County Surgical Associates

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 11 clinicians in the practice; 6 are shown here.

Other providers in Ventura