Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
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Dr. John Winston Duggan Jr., MD, MS

Individual provider Specialist · NPI 1851313514

Dr. John Winston Duggan Jr., MD, MS practises Ophthalmology in San Jose, California. Graduated from Tufts University School of Medicine in 1988, 38 years ago. Practices with Desert Ophthalmology Medical Corporation, a 5-clinician group and accepts Medicare assignment. Licensed in California.

Years since qualifying
38
Trained at
Tufts University School of Medicine
Licensed in
CA
In the registry since
2006
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.
MS — Master of Science
A graduate science degree.

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Practice location Address checks out

2516 Samaritan Dr Ste N
San Jose, CA 95124-4108
Phone: (408) 358-1600
Fax: (408) 358-1610
Show map & directions

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

Specialties & licences

Specialist (primary) Taxonomy 174400000X · Licence G683170 (CA)

Record details

NPI number1851313514
Entity typeIndividual (Type 1)
GenderMale
Credentials MD , MS
Sole proprietorYes
NPI enumeratedJuly 24, 2006
Last updated in NPPESApril 9, 2019

Medicare enrollment

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

Medicare specialtyOPHTHALMOLOGY
Medical schoolTUFTS UNIVERSITY SCHOOL OF MEDICINE
Graduated 1988 (38 years in practice)
Group practice Desert Ophthalmology Medical Corporation — 5 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.

Cataract surgery 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 patients78
Services billed 140 a service is one billed item, such as a visit, a test or a procedure
Average patient age70

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 Desert Ophthalmology Medical Corporation

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 5 clinicians in the practice; 2 are shown here.

Other providers in San Jose