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Internal Medicine

Dianna P. Ferguson, MD

Sees patients in Thousand Oaks, CA · Woodland Hills, CA · California

Summary

Dr. Dianna P. Ferguson, MD is an internal medicine doctor at 365 E Hillcrest Dr, Thousand Oaks, CA 91360. Phone: (805) 374-7433. Accepts Medicare assignment. In 2024, Dianna P. Ferguson had 11 Original Medicare patients and 23 services. NPI 1194826594. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Internal medicine doctor (Medicare lists Internal Medicine)
  • Address: 365 E Hillcrest Dr, Thousand Oaks, CA 91360 · Directions (1 more location)
  • Phone: (805) 374‑7433
  • Medicare: Accepts Medicare assignment
  • Group practice: Southern California Permanente Medical Group
  • Medical school: University Of California, San Diego School Of Medicine · graduated 1992 (34 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Dianna P. Ferguson, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Dianna P. Ferguson accept Medicare assignment?
Yes. Medicare's clinician data says Dianna P. Ferguson accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Dianna P. Ferguson see?
In 2024, CMS data shows 11 Original Medicare patients and 23 services for Dianna P. Ferguson. This counts Original Medicare only and measures volume, not quality.
What is Dianna P. Ferguson's NPI number?
1194826594. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Dianna P. Ferguson, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients11
Services billed to Medicare23
Different services or procedures10
Participating Medicare providerYes
Average age of these patients74

Practice locations

Addresses where Dianna P. Ferguson is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Dianna P. Ferguson as a member of this group (CMS data updated October 2, 2026).

  • Southern California Permanente Medical Group11,293 clinicians in the group

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in Thousand Oaks

Clinicians with the same Medicare primary specialty in Thousand Oaks, CA — not a recommendation.

All internal medicine doctors in Thousand Oaks →

Other clinicians in Southern California Permanente Medical Group

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialMD
Medical schoolUniversity Of California, San Diego School Of Medicine
Graduation year1992 (34 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1194826594
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  2. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians