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Internal Medicine

Catherine Diamond, MD

Works at hospitals in Orange, CA · California

Summary

Catherine Diamond, MD (Internal Medicine) is listed by Medicare at 1 hospital in Orange, CA. NPI 1649350786. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Catherine Diamond, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Internal MedicinePrimary specialty
YesAccepts Medicare assignment
YesOffers telehealth
35Years since medical school (graduated 1991)
Albany Medical College Of Union UniversityMedical school
FemaleGender (as listed)
UC RegentsGroup practice

Quick answers

Which hospitals does Catherine Diamond work at?
Medicare's official clinician data lists Catherine Diamond at 1 hospital: UCI Health-Orange. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Catherine Diamond see patients?
Medicare's clinician data lists 1 practice location in Orange, CA. Call before your visit to confirm the address.
What is Catherine Diamond's specialty?
Medicare lists Internal Medicine as the primary specialty, and also Infectious Disease.
Does Catherine Diamond accept Medicare assignment?
Yes. Medicare's clinician data says Catherine Diamond accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
Does Catherine Diamond offer telehealth?
Medicare's clinician data says Catherine Diamond offers telehealth services. Ask the office which visits can be done by video or phone.
What is Catherine Diamond's NPI number?
1649350786. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Catherine Diamond works

Medicare's Facility Affiliation Data lists Catherine Diamond at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where Catherine Diamond is enrolled with Medicare (CMS data updated 2026-10-02).

  • 101 the City Dr SOrange, CA 92868

Group practices

Medicare enrollment lists Catherine Diamond as a member of this group (CMS data updated 2026-10-02).

  • UC Regents319 clinicians in the group

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in Orange

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

All internal medicine doctors in Orange →

Clinician information

CredentialMD
Medical schoolAlbany Medical College Of Union University
Graduation year1991
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1649350786
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. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  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