William Chang, D.O.
NPI 1417902149 · Pulmonary Disease Physician · San Juan Capistrano, CA
Enrolled with Medicare as Practitioner - Pulmonary Disease · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Chang, D.O. is a Pulmonary Disease Physician provider in San Juan Capistrano, CA (NPI 1417902149).
Provider details
- NPI number
- 1417902149
- Entity type
- Individual
- Primary specialty
- Pulmonary Disease PhysicianAllopathic & Osteopathic Physicians
- Credential
- D.O.
- Sex
- Male
- Sole proprietor
- No
- License
- 20A7942 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Other Service Providers
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
20 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
5,736 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With High Level of Medical Decision Making, If Using Time, 40 Minutes Or More99215 | 1,305 | $198 |
| 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'SG2211 | 778 | $18 |
| Evaluation of Use of Breathing Device94664 | 399 | $21 |
| Telephone Medical Discussion With Physician, 21-30 Minutes99443 | 360 | $141 |
| Test to Examine How Well the Lungs Exchange Gases94729 | 314 | $67 |
| Test to Determine Lung Volumes Using Gas Dilution Or Washout94727 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 69 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Albuterol Sulfatebrand: Albuterol Sulfate Hfa | 745 | 280 |
| Fluticasone Propionate | 423 | 194 |
| Fluticasone/Umeclidin/Vilanterbrand: Trelegy Ellipta | 325 | 88 |
| Azelastine Hcl | 283 | 115 |
| Prednisone | 227 | 88 |
| Montelukast Sodium | 194 | 68 |
| Fluticasone Propion/Salmeterol |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$2,040 across 92 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-05-23
- Last updated
- 2013-04-17
Frequently asked questions
- What is William Chang's NPI number?
- William Chang's National Provider Identifier (NPI) is 1417902149, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Chang's specialty?
- William Chang is listed in the NPPES registry with a primary specialty of Pulmonary Disease Physician (Allopathic & Osteopathic Physicians).
- Where is William Chang located?
- William Chang's practice location on file with NPPES is 30230 Rancho Viejo Rd, San Juan Capistrano, CA 92675-1557.
- What is William Chang's phone number?
- The practice phone number listed in the NPPES registry for William Chang is (714) 571-5000.
- Does William Chang accept Medicare?
- William Chang is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Chang's NPI active?
- Yes — William Chang's NPI (1417902149) is active in the NPPES registry as of the last update on 2013-04-17.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.