Medicare Enrolled
Dr. William Chang, D.O.
Optician · San Juan Capistrano, CA
Practice pattern: Clinical Cardiology
— Primarily office-based clinical cardiology
Low-engagement
Very High
DATA COVERAGE
Data in 4 of 4 federal sources
Measures public federal data availability — not provider quality
Informational, not a quality rating.
This page presents federal public records about Dr. Chang from CMS (NPPES, Open Payments, Medicare Provider Utilization, PECOS). It is not medical advice, an endorsement, or a judgment of clinical quality. Always consult the provider directly and a licensed clinician for medical decisions. Read methodology →
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What this data tells you about Dr. Chang
Dr. William Chang is an optician specialist in San Juan Capistrano, CA, with 19 years of NPI registration. Based on federal Medicare data, Dr. Chang performed 4,864 Medicare services across 2,940 unique beneficiaries.
Between the years covered by Open Payments, Dr. Chang received a total of $14,416 from 54 pharmaceutical and/or device companies across 745 individual payments. These payments are legal, publicly disclosed under the federal Sunshine Act, and common in optician. 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.
✓ 19 years in practice
▲ Top 18% volume in CA
$14,416 industry payments
Medicare Practice Summary
Medicare Utilization ↗4,864
Medicare services
Top 18% in CA for optician
2,940
Unique beneficiaries
$80
Avg. Medicare payment
Medicare patients only (65+ / disabled) · How to read this →
~256 Medicare services per year of practice
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, 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. |
1,090 | $149 | $368 |
| Telephone or electronic consultation, at least 5 minutes A remote assessment and management service provided by a consulting physician via telephone, internet, or electronic health record. The service requires at least 5 minutes of time and includes a written report. |
767 | $30 | $88 |
| Telephone medical discussion, 21-30 minutes A telephone conversation with a physician lasting between 21 and 30 minutes. This code covers the time spent discussing medical matters over the phone. |
339 | $101 | $281 |
| Pulmonary gas exchange test A test to examine how well the lungs exchange gases. |
274 | $49 | $142 |
| Spirometry test before and after medication A test that measures the amount of air you can exhale and the speed of your breathing before and after taking a medication. |
268 | $33 | $148 |
| Breathing device use evaluation An assessment of how a patient uses a breathing device. The provider reviews the patient's technique and device handling. |
265 | $16 | $46 |
| Lung volume test using gas dilution or washout A test that measures the amount of air in your lungs by using a gas dilution or washout method. |
253 | $38 | $109 |
| 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. |
226 | $105 | $263 |
| Critical care, first 30-74 min Emergency medical care for a critically ill or injured patient lasting between 30 and 74 minutes. This service involves direct patient care and medical decision making to stabilize the patient. |
216 | $174 | $644 |
| Exercise-induced lung stress test A test performed to evaluate how the lungs function during physical exertion. It helps identify breathing difficulties or lung conditions that occur specifically when exercising. |
187 | $29 | $84 |
| Hospital follow-up visit, high complexity Subsequent hospital inpatient or observation care for an existing patient involving high-level medical decision making, with at least 50 minutes total time on the date of the encounter. |
179 | $100 | $248 |
| Expiratory airflow and volume test A test that measures the amount of air you can exhale and the speed at which you can breathe it out. It evaluates lung function by assessing expiratory airflow and volume. |
140 | $22 | $90 |
| Advance care planning consultation, first 30 min A session focused on discussing and documenting future healthcare preferences and goals. This service covers the initial 30 minutes of the planning discussion. |
124 | $70 | $192 |
| Airflow rate measurement test A test that measures the rate of airflow. This procedure assesses how quickly air moves. |
77 | $34 | $99 |
| Prolonged office E/M service, first 15 minutes This code is used for additional time spent by a physician beyond the maximum required time of a primary office or outpatient evaluation and management service. It is billed in 15-minute increments based on total time spent on the date of the primary service. |
71 | $26 | $78 |
| New patient office visit, complex (60-74 min) | 70 | $187 | $493 |
| Telephone medical discussion, 11-20 minutes A phone conversation with a physician lasting between 11 and 20 minutes. |
47 | $74 | $190 |
| Nitric oxide gas level test A test that measures the level of nitric oxide gas in the body. |
44 | $18 | $49 |
| Sleep study with heart rate and breathing monitoring A sleep study that monitors heart rate, breathing, airflow, and physical effort during sleep. |
40 | $82 | $381 |
| Additional 30 minutes of critical care This code represents an additional 30 minutes of critical care services provided beyond the initial critical care time period. |
37 | $89 | $284 |
| Virtual check-in for established patient A brief communication service provided by a qualified healthcare professional to an established patient via technology, such as a virtual check-in. |
25 | $7 | $35 |
| Initial hospital admission, high complexity Initial hospital inpatient or observation care for a new patient involving high-level medical decision making, with at least 75 minutes total time on the date of the encounter. |
23 | $145 | $446 |
| Lung volume test using sensors A test that measures the amount of air in the lungs using sensors. |
20 | $48 | $140 |
| Flu vaccine, high-dose High-dose seasonal influenza vaccine for adults aged 65 and older. Contains four times the antigen of standard-dose flu vaccines (60 mcg per strain), split-virus formulation, preservative-free, single-dose syringe. |
19 | $64 | $97 |
| Flu vaccine administration This procedure involves the administration of the influenza virus vaccine. It covers the process of delivering the vaccine to the patient. |
19 | $33 | $63 |
| 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. |
15 | $65 | $179 |
| Hospital discharge management, 30+ min This service covers the care provided by a physician or qualified healthcare professional on the day a patient is discharged from the hospital. It requires more than 30 minutes of total time spent on the day of discharge. |
15 | $97 | $267 |
| Spirometry test A test that measures the amount of air you can exhale and how fast you can blow it out. The provider evaluates the results to check lung function. |
14 | $20 | $58 |
How to read this data: This reflects Medicare patients only (typically 65+). Payment amounts are what Medicare paid the provider, not your out-of-pocket cost. A higher procedure volume generally indicates more experience with that procedure.
Industry Payment Transparency
Open Payments through 2024 ↗$14,416
Total received (2018-2024)
Avg $2,059/year across 7 years
Top 10% in CA for optician
A higher payment rank reflects disclosed industry relationships (consulting, research, speaking) common among subspecialists — not wrongdoing.
54
Companies
745
Individual payments
All payments are legal and publicly reported · Not evidence of wrongdoing · How to interpret →
Payment profile
Industry payments classified by relationship type. Not all payments are equal — research and consulting reflect different relationships than speaking programs or meals.
Meals & Travel
Food, beverages, travel, and lodging — typically low-value
$14,191 (98.4%)
Speaking / Promotional
Speaker programs, honoraria, and industry-sponsored educational events
$225 (1.6%)
Payment trend by year
Annual totals from pharmaceutical and medical device companies.
2024
$2,040
2023
$2,375
2022
$1,575
2021
$1,771
2020
$910
2019
$3,254
2018
$2,491
Payments by company (2024)
Consulting
Speaking
Meals & Travel
Research
GlaxoSmithKline, LLC.
$535
AstraZeneca Pharmaceuticals LP
$302
United Therapeutics Corporation
$298
Vifor Pharma, Inc.
$113
Boehringer Ingelheim Pharmaceuticals, Inc.
$108
Insmed, Inc.
$103
Avadel CNS Pharmaceuticals, LLC
$91
GENZYME CORPORATION
$81
PFIZER INC.
$64
Grifols USA, LLC
$63
Axsome Therapeutics, Inc.
$53
Mylan Specialty L.P.
$52
Exact Sciences Corporation
$29
Harmony Biosciences Llc
$29
Regeneron Healthcare Solutions, Inc.
$26
JAZZ PHARMACEUTICALS INC.
$23
Electromed, Inc.
$20
Lilly USA, LLC
$18
CMP Pharma, Inc.
$17
Pulmonx Corporation
$15
Top 3 companies account for 55.6% of 2024 payments
All-time payments by company (2018-2024) ›
GlaxoSmithKline, LLC.
$3,638
Boehringer Ingelheim Pharmaceuticals, Inc.
$2,358
AstraZeneca Pharmaceuticals LP
$1,675
Insmed, Inc.
$772
Grifols USA, LLC
$671
GENZYME CORPORATION
$616
Genentech USA, Inc.
$509
United Therapeutics Corporation
$415
Regeneron Healthcare Solutions, Inc.
$388
Philips Electronics North America Corporation
$359
Harmony Biosciences LLC
$356
JAZZ PHARMACEUTICALS INC.
$322
Janssen Pharmaceuticals, Inc
$262
Actelion Pharmaceuticals US, Inc.
$209
Mylan Specialty L.P.
$201
Avadel CNS Pharmaceuticals, LLC
$117
Vifor Pharma, Inc.
$113
Shire North American Group Inc
$105
SANOFI-AVENTIS U.S. LLC
$98
Takeda Pharmaceuticals U.S.A., Inc.
$88
Advanced Respiratory, Inc
$88
Circassia Pharmaceuticals Inc
$78
PFIZER INC.
$75
E.R. Squibb & Sons, L.L.C.
$65
Amgen Inc.
$59
Electromed, Inc.
$55
Pulmonx Corporation
$55
Axsome Therapeutics, Inc.
$53
Jazz Pharmaceuticals Inc.
$49
Mallinckrodt Hospital Products Inc.
$47
Exact Sciences Corporation
$46
AbbVie Inc.
$45
Novo Nordisk Inc
$36
Covis Pharma GmBH
$34
Harmony Biosciences Llc
$29
Baxter Healthcare
$29
Boston Scientific Corporation
$26
Phadia US Inc.
$22
HARMONY BIOSCIENCES LLC
$21
Allergan Inc.
$19
Salix Pharmaceuticals, a division of Bausch Health US, LLC
$18
Lilly USA, LLC
$18
Vertical Pharmaceuticals, LLC
$17
CSL Behring
$17
Sanofi Pasteur Inc.
$17
CMP Pharma, Inc.
$17
BOSTON SCIENTIFIC CORPORATION
$16
Vertiflex, Inc.
$15
SANOFI PASTEUR INC.
$14
Merck Sharp & Dohme Corporation
$14
Medtronic MiniMed, Inc.
$14
Bayer HealthCare Pharmaceuticals Inc.
$13
Purdue Pharma L.P.
$13
Endogastric Solutions, Inc
$13
Top 3 companies account for 53.2% of all-time payments
Associated products mentioned in payments ›
(8874) inCourage · (9360) DS2A A cell FG · ACTHAR · ADACEL · AIRSUPRA · ALVESCO · ANORO · ANORO ELLIPTA · AVYCAZ · Adempas · Arikayce · Atorvaliq · BEVESPI AEROSPHERE · BEXSERO · BREO · BREO ELLIPTA · BREZTRI · CHARTIS CATHETER · CINRYZE · CUVITRU · Cologuard Collection Kit · DUPIXENT · Dymista · ELIQUIS · EMBLEM MRI S-ICD · ESOPHYX · Esbriet · FASENRA · GLASSIA · HYQVIA · Hillrom - Life 2000 Ventilation System · ImmunoCAP · JANUVIA · JARDIANCE · LOKELMA · LUMRYZ · LUX DX · NO PRODUCT DISCUSSED · NUCALA · OFEV · OPSUMIT · OPSUMIT MACITENTAN · Ozempic · PREVNAR 20 · Prolastin-C · Prolastin-C Liquid · Pulmonx Endobronchial Valve EBV · RELEXXII · Respiratoriy Care Undiv · Rybelsus · S&RC Und · SHINGRIX · SMARTVEST · SOLIQUA · SPIRIVA RESPIMAT · SRC Und · STIOLTO RESPIMAT · SUNOSI · SYMBICORT · Sunosi · Superion ISS · TEFLARO · TEZSPIRE · TRELEGY ELLIPTA · TUDORZA PRESSAIR · TYVASO · The Monarch Airway Clearance System · The Vest System Model 105 Home Care · The VitalCough System · UBRELVY · UPTRAVI · WAKIX · Wakix · XARELTO · XIFAXAN · XYREM · XYWAV · Xolair · Xyrem · YUPELRI · Yupelri · Zemaira · iPro2 · inCourage
Should you be concerned? Payments from pharmaceutical and device companies are legal and common — 57% of U.S. physicians receive at least one. They often reflect legitimate consulting, research, or education. What matters is whether a recommended drug or device appears in your doctor's payment records. If so, consider asking your doctor about it. How to interpret this data →
Most payments (98%) 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 optician in CA.
Geographic Context
Opticians within 10 mi
461
Per 100K population
14.6
County median income
$113,702
Nearest hospital
ALISO RIDGE BEHAVIORAL HEALTH, LLC
6.8 mi
6.8 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 18% 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 office visit, established patient, complex (40-54 min)?
Based on Medicare claims data, Dr. Chang performed 1,090 office visit, established patient, complex (40-54 min) services. Research suggests that higher procedure volume is often associated with better outcomes, particularly for complex procedures. Note that Medicare data only captures patients aged 65 and older, so the total practice volume across all patients is likely higher.
Does Dr. Chang receive payments from pharmaceutical companies?
Yes. Dr. Chang received a total of $14,416 from 54 companies across 745 individual payments. These payments are legal, publicly disclosed under the federal Sunshine Act, and common among physicians — 57% of all U.S. physicians receive at least one industry payment. Patients may wish to ask their doctor about these relationships, especially if a recommended drug or device appears in the payment records.
How do Dr. Chang's costs compare to other opticians in San Juan Capistrano?
Dr. Chang's average Medicare payment per service is $80. Note that these figures represent what Medicare pays, not your out-of-pocket cost, which depends on your specific insurance plan and deductible. Procedure-level data above shows both what was submitted and what Medicare paid for each service type.
What does Data Coverage mean?
Data Coverage (currently Very High for Dr. Chang) measures how much public federal data is available about a provider. It is not a quality rating. A "Very High" or "High" level means the provider has data across multiple federal sources (NPPES, PECOS, Medicare Utilization, Open Payments), indicating a long track record of practice, Medicare participation, and industry disclosure. A "Low" or "Moderate" level may simply mean the provider is newer, does not see Medicare patients, or has not received any industry payments — none of which are inherently negative. Read our full methodology →
Is this data up to date?
Each data source has its own update cycle. Provider registry data (NPPES) is updated weekly. Medicare enrollment (PECOS) is updated monthly. Medicare practice data has a ~2 year lag — the most recent available is typically 2 years prior. Industry payment data (Open Payments) is published annually, usually in June, covering the prior calendar year. We display the data date prominently on each section so you always know how current it is. See our data freshness policy →
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About this page
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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