John Chang, D.O.
NPI 1679557326 · Emergency Medicine Physician · Lawrence, MA
Enrolled with Medicare as Practitioner - Emergency Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
John Chang, D.O. is a Emergency Medicine Physician provider in Lawrence, MA (NPI 1679557326).
Provider details
- NPI number
- 1679557326
- Entity type
- Individual
- Primary specialty
- Emergency Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- D.O.
- Sex
- Male
- Sole proprietor
- No
- License
- 56184 (MA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure33% of score
20 yrs in NPPES registry
- Profile completeness33% of score
100% of core fields populated
- Practice footprint20% of score
1 documented practice location
- Open Payments transparency13% of score
Has Open Payments disclosures (2024)
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.
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$69 across 2 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
- 2005-12-05
- Last updated
- 2020-09-25
- Certified
- 2020-09-25
Frequently asked questions
- What is John Chang's NPI number?
- John Chang's National Provider Identifier (NPI) is 1679557326, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is John Chang's specialty?
- John Chang is listed in the NPPES registry with a primary specialty of Emergency Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is John Chang located?
- John Chang's practice location on file with NPPES is 34 Haverhill St, Lawrence, MA 01841-2884.
- What is John Chang's phone number?
- The practice phone number listed in the NPPES registry for John Chang is (978) 686-0090.
- Does John Chang accept Medicare?
- John Chang is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is John Chang's NPI active?
- Yes — John Chang's NPI (1679557326) is active in the NPPES registry as of the last update on 2020-09-25.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.