Quick answers
- Does Diana J. Chang accept Medicare assignment?
- Yes. Medicare's clinician data says Diana J. Chang 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 Diana J. Chang see?
- In 2024, CMS data shows 292 Original Medicare patients and 7,318 services for Diana J. Chang. This counts Original Medicare only and measures volume, not quality.
- What is Diana J. Chang's NPI number?
- 1396142386. 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 Diana J. Chang, 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 | 292 |
|---|---|
| Services billed to Medicare | 7,318 |
| Different services or procedures | 26 |
| Participating Medicare provider | Yes |
| Average age of these patients | 73 |
Most frequent services
- Injection, denosumab, 1 mg (J0897)1,980 services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)372 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)352 services
- Blood glucose (sugar) level (82947)161 services
- Hemoglobin a1c level (83036)160 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%
- Diabetes56%
- Arthritis55%
- Ischemic heart disease40%
- Osteoporosis39%
Hospitals where Diana J. Chang works
Medicare's Facility Affiliation Data lists Diana J. Chang 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.
- Ronald Reagan UCLA Medical CenterLos Angeles, CA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 050262
- Santa Monica - UCLA Medical Center & Orthopaedic HospitalSanta Monica, CA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 050112
- UCLA West Valley Medical CenterWest Hills, CA · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 050481
Practice locations
Addresses where Diana J. Chang is enrolled with Medicare (CMS data updated October 2, 2026).
- 19950 Rinaldi StPorter Ranch, CA 91326
- 200 UCLA Medical PlzLos Angeles, CA 90095
- 2020 Santa Monica Blvd, Suite 210Santa Monica, CA 90404 (310) 458‑2381
- 2020 Santa Monica Blvd, Suite 550Santa Monica, CA 90404
- 700 W 7th St, S270 DLos Angeles, CA 90017 (213) 896‑0010
Group practices
Medicare enrollment lists Diana J. Chang as a member of this group (CMS data updated October 2, 2026).
- The Regents of the University of California1,462 clinicians in the group
Specialties
- Endocrinologyprimary
Other endocrinologists in Porter Ranch
Clinicians with the same Medicare primary specialty in Porter Ranch, CA — not a recommendation.
Other clinicians in The Regents of the University of California
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of California, Davis School Of Medicine |
| Graduation year | 2016 (10 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1396142386 |
| 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