John Constantine, M.D.
NPI 1437157765 · Ophthalmology Physician · Chelmsford, MA
John Constantine, M.D. is a Ophthalmology Physician provider in Chelmsford, MA (NPI 1437157765).
Provider details
- NPI number
- 1437157765
- Entity type
- Individual
- Primary specialty
- Ophthalmology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- 71751 (MA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Other Service Providers
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
- 2005-07-11
- Last updated
- 2011-09-29
Frequently asked questions
- What is John Constantine's NPI number?
- John Constantine's National Provider Identifier (NPI) is 1437157765, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is John Constantine's specialty?
- John Constantine is listed in the NPPES registry with a primary specialty of Ophthalmology Physician (Allopathic & Osteopathic Physicians).
- Where is John Constantine located?
- John Constantine's practice location on file with NPPES is 19 Village Sq, Chelmsford, MA 01824-2712.
- What is John Constantine's phone number?
- The practice phone number listed in the NPPES registry for John Constantine is (978) 256-5600.
- Is John Constantine's NPI active?
- Yes — John Constantine's NPI (1437157765) is active in the NPPES registry as of the last update on 2011-09-29.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.