John Sia, MD
NPI 1912958281 · Internal Medicine Physician · Lincolnwood, IL
Enrolled with Medicare as Order and Referring Only - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
John Sia, MD is a Internal Medicine Physician provider in Lincolnwood, IL (NPI 1912958281).
Provider details
- NPI number
- 1912958281
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- Yes
- License
- 036-083555 (IL)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
20 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
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
Registry dates
- Enumerated
- 2006-05-12
- Last updated
- 2010-10-05
Frequently asked questions
- What is John Sia's NPI number?
- John Sia's National Provider Identifier (NPI) is 1912958281, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is John Sia's specialty?
- John Sia is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is John Sia located?
- John Sia's practice location on file with NPPES is 6641 N Dowagiac Ave, Lincolnwood, IL 60712-3021.
- What is John Sia's phone number?
- The practice phone number listed in the NPPES registry for John Sia is (847) 208-7995.
- Does John Sia accept Medicare?
- John Sia is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is John Sia's NPI active?
- Yes — John Sia's NPI (1912958281) is active in the NPPES registry as of the last update on 2010-10-05.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.