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Emergency Medicine

Cassandra N. Mackey, MD

Works at hospitals in Leominster, MA · Worcester, MA · Massachusetts

Summary

Cassandra N. Mackey, MD (Emergency Medicine) is listed by Medicare at 2 hospitals in Leominster, MA and Worcester, MA. NPI 1578927554. 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 Cassandra N. Mackey, 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

Emergency MedicinePrimary specialty
YesAccepts Medicare assignment
10Years since medical school (graduated 2016)
New York Medical CollegeMedical school
FemaleGender (as listed)
UMass Memorial Medical Group IncGroup practice

Quick answers

Which hospitals does Cassandra N. Mackey work at?
Medicare's official clinician data lists Cassandra N. Mackey at 2 hospitals: UMass Memorial Healthalliance Hospitals and UMass Memorial Medical Center/University Campus. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Cassandra N. Mackey see patients?
Medicare's clinician data lists 1 practice location in Worcester, MA. Call before your visit to confirm the address.
What is Cassandra N. Mackey's specialty?
Medicare lists Emergency Medicine as the primary specialty.
Does Cassandra N. Mackey accept Medicare assignment?
Yes. Medicare's clinician data says Cassandra N. Mackey 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.
What is the phone number for Cassandra N. Mackey?
(508) 334-1000, as listed in official Medicare / NPI Registry data.
What is Cassandra N. Mackey's NPI number?
1578927554. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Cassandra N. Mackey works

Medicare's Facility Affiliation Data lists Cassandra N. Mackey 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 Cassandra N. Mackey is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Cassandra N. Mackey as a member of this group (CMS data updated 2026-10-02).

  • UMass Memorial Medical Group Inc2,516 clinicians in the group

Specialties

Find other Emergency Medicine doctors in Massachusetts →

Other emergency medicine doctors in Worcester

Clinicians with the same Medicare primary specialty in Worcester, MA — not a recommendation.

All emergency medicine doctors in Worcester →

Clinician information

CredentialMD
Medical schoolNew York Medical College
Graduation year2016
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1578927554
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