Dr. Anna Chang, M.D.
What this data tells you about Dr. Chang
Dr. Anna Chang is an internal medicine specialist in Concord, CA, with 19 years of NPI registration. Based on federal Medicare data, Dr. Chang performed 3,651 Medicare services across 1,027 unique beneficiaries.
Between the years covered by Open Payments, Dr. Chang received a total of $9,753 from 21 pharmaceutical and/or device companies across 135 individual payments. These payments are legal, publicly disclosed under the federal Sunshine Act, and common in internal medicine. Most payments are for meals and travel — low-value interactions common across virtually all practicing physicians. Patients may wish to discuss these relationships with their provider.
The Data Coverage level for Dr. Chang is Very High — reflecting how much public federal data is available about this provider. Patients are encouraged to use this data as one of several factors when choosing a healthcare provider.
Medicare Practice Summary
Medicare Utilization ↗Top procedures by volume
Ranked by number of services performed for Medicare patients. Avg. submitted charge is what the provider billed; avg. Medicare payment is what CMS paid.
| Procedure | Volume | Avg. paid | Avg. submitted |
|---|---|---|---|
| Denosumab injection (Prolia/Xgeva) | 1,620 | $17 | $50 |
| Diabetes self-management training, individual Individualized education and training for managing diabetes, billed per 30-minute session. |
728 | $48 | $128 |
| Office visit, established patient (30-39 min) A follow-up office visit for an existing patient lasting between 30 and 39 minutes. The visit involves medical evaluation and management of the patient's condition. |
353 | $101 | $305 |
| Hemoglobin A1c test (diabetes monitoring) A blood test that measures your average blood sugar levels over the past two to three months. |
202 | $9 | $54 |
| Zoledronic acid injection, 1 mg An injection of zoledronic acid administered at a dose of 1 mg. |
191 | $7 | $515 |
| Office visit, established patient (20-29 min) An office visit for an existing patient lasting between 20 and 29 minutes. The visit involves medical evaluation and management of the patient's condition. |
190 | $70 | $210 |
| Continuous glucose monitoring with interpretation This procedure involves monitoring blood sugar levels in tissue fluid using a sensor placed under the skin, along with the interpretation and reporting of the results. |
136 | $31 | $121 |
| Diabetes self-management training, group session A group educational session for diabetes management involving two or more participants. The service is billed in 30-minute increments. |
127 | $15 | $54 |
| Drug injection, under skin or into muscle A procedure involving the administration of a medication or substance via injection into the subcutaneous tissue or muscle. |
45 | $13 | $75 |
| Intravenous infusion, 1 hour or less Administration of medication or fluid directly into a vein for therapeutic, preventive, or diagnostic purposes. The procedure lasts one hour or less. |
39 | $60 | $244 |
| Telephone medical discussion, 11-20 minutes A phone conversation with a physician lasting between 11 and 20 minutes. |
20 | $48 | $210 |
Industry Payment Transparency
Open Payments through 2024 ↗Payment profile
Industry payments classified by relationship type. Not all payments are equal — research and consulting reflect different relationships than speaking programs or meals.
Payment trend by year
Annual totals from pharmaceutical and medical device companies.
Payments by company (2024)
All-time payments by company (2018-2024) ›
Associated products mentioned in payments ›
Most payments (99%) are for meals and travel — low-value interactions that are common across virtually all practicing physicians. Total industry engagement is in the top 10% for internal medicine in CA.
Geographic Context
0.0 mi
Data Sources
| Provider Registry | ✓ NPPES | Weekly updates |
| Medicare Enrollment | ✓ PECOS | Monthly updates |
| Practice Data | ✓ Medicare Util. | Annual (CY lag) |
| Industry Payments | ✓ Open Payments | CY 2024 |
| Disciplinary History | — Not public | N/A |
This provider has data in 4 of 4 available federal datasets, with a Data Coverage level of Very High. This reflects how much public data is available about a provider. How we calculate this →
Summary
Dr. Chang is a clinical cardiology specialist, with above-average Medicare volume (top 8% in CA), with low-engagement industry engagement in the top 10% of CA peers, with 19 years of NPI registration.
This summary is auto-generated from federal data, describing data availability and patterns. Read our methodology →
Frequently Asked Questions
Is Dr. Chang experienced with denosumab injection (prolia/xgeva)?
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All data on this page is sourced verbatim from public federal records published by the U.S. Centers for Medicare & Medicaid Services (CMS): NPPES ↗, Open Payments ↗, Medicare Provider Utilization ↗, and PECOS. Publication is mandated by the Physician Payments Sunshine Act (§6002 ACA, 42 U.S.C. §1320a-7h) and the Freedom of Information Act.
This page is not medical advice, an endorsement, a recommendation, or a quality rating. Data Coverage reflects data completeness — how much federal information exists for this provider — not clinical performance, patient outcomes, or quality of care. Always verify information directly with the provider and consult a licensed clinician before making medical decisions.
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