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Emergency Medicine

Rebecca B. Parker, MD

Works at hospitals in Tucson, AZ · Arizona

Summary

Dr. Rebecca B. Parker, MD is an emergency medicine doctor at 5301 E Grant Rd, Tucson, AZ 85712. Phone: (520) 327-5461. Accepts Medicare assignment. In 2024, Rebecca B. Parker had 112 Original Medicare patients and 162 services. NPI 1255373494. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Emergency medicine doctor (Medicare lists Emergency Medicine)
  • Address: 5301 E Grant Rd, Tucson, AZ 85712 · Directions
  • Phone: (520) 327‑5461
  • Medicare: Accepts Medicare assignment
  • Hospital: Tucson Medical Center
  • Group practice: Ies Arizona PLLC
  • Medical school: Northwestern University Feinberg Medical School · graduated 1995 (31 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Rebecca B. Parker, 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 Rebecca B. Parker accept Medicare assignment?
Yes. Medicare's clinician data says Rebecca B. Parker 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 Rebecca B. Parker see?
In 2024, CMS data shows 112 Original Medicare patients and 162 services for Rebecca B. Parker. This counts Original Medicare only and measures volume, not quality.
What is Rebecca B. Parker's NPI number?
1255373494. 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 Rebecca B. Parker, 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 patients112
Services billed to Medicare162
Different services or procedures9
Participating Medicare providerYes
Average age of these patients77

Most frequent services

  1. Emergency department visit with high level of medical decision making (99285)75 services
  2. Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only (93010)46 services
  3. Critical care, first 30-74 minutes (99291)18 services
  4. Emergency department visit with moderate level of medical decision making (99284)17 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure75%
  • High cholesterol75%
  • Arthritis66%
  • Ischemic heart disease45%
  • Chronic kidney disease40%
  • Depression39%

Hospitals where Rebecca B. Parker works

Medicare's Facility Affiliation Data lists Rebecca B. Parker at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

  • Tucson Medical CenterTucson, AZ · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 030006

Practice locations

Addresses where Rebecca B. Parker is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Rebecca B. Parker as a member of this group (CMS data updated October 2, 2026).

  • Ies Arizona PLLC52 clinicians in the group

Specialties

Find other Emergency Medicine doctors in Arizona →

Other emergency medicine doctors in Tucson

Clinicians with the same Medicare primary specialty in Tucson, AZ — not a recommendation.

All emergency medicine doctors in Tucson →

Other clinicians in Ies Arizona PLLC

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

Clinician information

CredentialMD
Medical schoolNorthwestern University Feinberg Medical School
Graduation year1995 (31 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1255373494
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 October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians