Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
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Mark J Tamsen, MD

Individual provider Emergency Medicine Physician · NPI 1346241452

Mark J Tamsen, MD practises Emergency Medicine in San Diego, California. Graduated from University of Arizona College of Medicine in 1979, 47 years ago. Practices with Emergency Care Dynamics Inc, a 2-clinician group and accepts Medicare assignment. Licensed in California.

Years since qualifying
47
Trained at
University of Arizona College of Medicine
Licensed in
CA
In the registry since
2005
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

3434 Midway Dr Ste 1002
San Diego, CA 92110-4924
Phone: (619) 225-6200
Fax: (619) 225-6208
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Emergency Medicine Physician (primary) Taxonomy 207P00000X · Licence G64400 (CA)

Record details

NPI number1346241452
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedAugust 10, 2005
Last updated in NPPESDecember 16, 2020
Certification dateDecember 16, 2020

Medicare enrollment

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

Medicare specialtyEMERGENCY MEDICINE
Also practisesINTERNAL MEDICINE
Medical schoolUNIVERSITY OF ARIZONA COLLEGE OF MEDICINE
Graduated 1979 (47 years in practice)
Group practice Emergency Care Dynamics Inc — 2 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

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 tissue 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 patients316
Services billed 1,100 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.

Colleagues at Emergency Care Dynamics Inc

Clinicians the CMS Doctors & Clinicians file lists under the same group practice.

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