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Clinical Psychologist

Rachel Z. Ishikawa

Works at hospitals in Boston, MA · Massachusetts

Summary

Rachel Z. Ishikawa is a clinical psychologist at 1575 Cambridge St, Cambridge, MA 02138. Phone: (617) 876-4344. Accepts Medicare assignment. In 2024, Rachel Z. Ishikawa had 40 Original Medicare patients and 516 services. NPI 1942646138. 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: Clinical psychologist
  • Address: 1575 Cambridge St, Cambridge, MA 02138 · Directions (1 more location)
  • Phone: (617) 876‑4344
  • Medicare: Accepts Medicare assignment
  • Hospital: Massachusetts General Hospital
  • Group practice: Massachusetts General Physicians Organization Inc (+1 more)
  • School: graduated 2013
  • Gender (as listed): Female
  • Telehealth: offered

From official Medicare data

This page shows what Medicare's official clinician data says about Rachel Z. Ishikawa, 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 Rachel Z. Ishikawa accept Medicare assignment?
Yes. Medicare's clinician data says Rachel Z. Ishikawa 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 Rachel Z. Ishikawa see?
In 2024, CMS data shows 40 Original Medicare patients and 516 services for Rachel Z. Ishikawa. This counts Original Medicare only and measures volume, not quality.
What is Rachel Z. Ishikawa's NPI number?
1942646138. 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 Rachel Z. Ishikawa, 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 patients40
Services billed to Medicare516
Different services or procedures5
Participating Medicare providerYes
Average age of these patients74

Most frequent services

  1. Psychotherapy, 1 hour (90837)248 services
  2. Psychiatric services complicated by communication factor (90785)135 services
  3. Psychotherapy, 45 minutes (90834)97 services
  4. Psychotherapy, 30 minutes (90832)16 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 cholesterol75%
  • Depression75%
  • Anxiety75%
  • High blood pressure63%
  • Arthritis53%
  • Ischemic heart disease33%

Hospitals where Rachel Z. Ishikawa works

Medicare's Facility Affiliation Data lists Rachel Z. Ishikawa 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.

Practice locations

Addresses where Rachel Z. Ishikawa is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Rachel Z. Ishikawa as a member of these groups (CMS data updated October 2, 2026).

  • Massachusetts General Physicians Organization Inc3,558 clinicians in the group
  • The General Hospital Corporation1,267 clinicians in the group

Specialties

Find other clinicians: Clinical Psychologist, Massachusetts →

Other clinical psychologists in Cambridge

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

All clinical psychologists in Cambridge →

Other clinicians in Massachusetts General Physicians Organization Inc

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

Clinician information

Graduation year2013
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1942646138
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