Dr. Andy Chang, MD
What this data tells you about Dr. Chang
Dr. Andy Chang is a family medicine specialist in Fremont, CA, with 19 years of NPI registration. Based on federal Medicare data, Dr. Chang performed 529 Medicare services across 376 unique beneficiaries.
Between the years covered by Open Payments, Dr. Chang received a total of $2,050 from 9 pharmaceutical and/or device companies across 14 individual payments. These payments are legal, publicly disclosed under the federal Sunshine Act, and common in family medicine. The majority of payments are for consulting, which typically reflects recognized clinical expertise sought by manufacturers. 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 |
|---|---|---|---|
| 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. |
283 | $102 | $364 |
| Annual wellness visit, follow-up A follow-up annual wellness visit that includes a personalized prevention plan of service. |
99 | $157 | $167 |
| 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. |
81 | $70 | $247 |
| Office visit, established patient, complex (40-54 min) An office or outpatient visit for an existing patient lasting between 40 and 54 minutes. This level of service is determined by the total time spent on the date of the encounter. |
28 | $168 | $489 |
| Flu vaccine, quadrivalent A flu shot containing four strains of the influenza virus to help prevent seasonal influenza infection. |
14 | $75 | $90 |
| Flu vaccine administration This procedure involves the administration of the influenza virus vaccine. It covers the process of delivering the vaccine to the patient. |
12 | $37 | $65 |
| Pneumonia vaccine administration This procedure involves the injection of a vaccine to protect against pneumococcal disease. It is administered by a healthcare provider. |
12 | $35 | $35 |
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 (2019-2024) ›
Associated products mentioned in payments ›
The majority of payments (84%) are consulting fees, which typically reflect recognized clinical expertise sought by manufacturers.
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 moderate Medicare volume, with consulting-driven industry engagement in the top 17% 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
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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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