Chih Yao Chang, MD
NPI 1730820739 · Internal Medicine Physician · San Francisco, CA
Enrolled with Medicare as Practitioner - Hospitalist · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Chih Yao Chang, MD is a Internal Medicine Physician provider in San Francisco, CA (NPI 1730820739).
Provider details
- NPI number
- 1730820739
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Student, Health Care
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
4 yrs in NPPES registry
- Profile completeness38% of score
83% of core fields populated
- Practice footprint23% of score
2 documented practice locations
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 methodology.
Practice location
Mailing address
Additional practice locations (1)
- St. Mary'S Medical Center450 Stanyan StreetSan Francisco, CA 94117Phone: (415) 750-5942Fax: (415) 750-5594
Registry dates
- Enumerated
- 2022-04-05
- Last updated
- 2025-05-15
- Certified
- 2025-05-15
Frequently asked questions
- What is Chih Yao Chang's NPI number?
- Chih Yao Chang's National Provider Identifier (NPI) is 1730820739, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Chih Yao Chang's specialty?
- Chih Yao Chang is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Chih Yao Chang located?
- Chih Yao Chang's practice location on file with NPPES is 521 Parnassus Ave, San Francisco, CA 94143-2206.
- What is Chih Yao Chang's phone number?
- The practice phone number listed in the NPPES registry for Chih Yao Chang is (415) 750-5942.
- Does Chih Yao Chang accept Medicare?
- Chih Yao Chang is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Chih Yao Chang's NPI active?
- Yes — Chih Yao Chang's NPI (1730820739) is active in the NPPES registry as of the last update on 2025-05-15.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.