Quick answers
- Does Arley F. Diaz accept Medicare assignment?
- Yes. Medicare's clinician data says Arley F. Diaz 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 Arley F. Diaz see?
- In 2024, CMS data shows 880 Original Medicare patients and 4,269 services for Arley F. Diaz. This counts Original Medicare only and measures volume, not quality.
- What is Arley F. Diaz's NPI number?
- 1093706525. 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 Arley F. Diaz, 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 patients | 880 |
|---|---|
| Services billed to Medicare | 4,269 |
| Different services or procedures | 22 |
| Participating Medicare provider | Yes |
| Average age of these patients | 75 |
Most frequent services
- Injection, epoetin alfa-epbx, biosimilar, (retacrit) (for non-esrd use), 1000 units (Q5106)982 services
- Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's (G2211)849 services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)750 services
- Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)591 services
- Dialysis services, 4 or more physician visits per month (20 years or older) (90960)248 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%
- Chronic kidney disease75%
- High cholesterol73%
- Diabetes47%
- Arthritis40%
- Heart failure37%
Hospitals where Arley F. Diaz works
Medicare's Facility Affiliation Data lists Arley F. Diaz 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.
- Baystate Medical CenterSpringfield, MA · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 220077
- Holyoke Medical CenterHolyoke, MA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 220024
- Massachusetts General HospitalBoston, MA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 220071
- The Cooley Dickinson Hospital IncNorthampton, MA · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 220015
Practice locations
Addresses where Arley F. Diaz is enrolled with Medicare (CMS data updated October 2, 2026).
- 208 Ashley AveWest Springfield, MA 01089 (413) 733‑0010
Group practices
Medicare enrollment lists Arley F. Diaz as a member of this group (CMS data updated October 2, 2026).
- Kidney Care and Transplant Services of New England PC14 clinicians in the group
Specialties
- Nephrologyprimary
Other nephrologists in West Springfield
Clinicians with the same Medicare primary specialty in West Springfield, MA — not a recommendation.
Other clinicians in Kidney Care and Transplant Services of New England PC
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1994 (32 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1093706525 |
| Corrections | Report 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
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians