Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum
Dr. Gary John Nielan
Pediatric Adolescent Medicine Physician in Wilbraham, MA · enumerated 2005.
Data current as of Jul 13, 2026 · sourced from CMS NPPES
National Provider Identifier
1568458479
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Registry record
Taxonomy & licenses
Other identifiers
| Identifier | Type | State | Issuer |
|---|---|---|---|
| 2017078 | Other | - | AETNA/USHC |
| 155058 | Other | - | MA LICENSE |
| 23378 | Other | - | HEALTH NEW ENGLAND |
| 28036 | Other | - | CHILDRENS MEDICAL SECURIT |
| 353451 | Other | - | HEALTHSOURCE MA NH |
| J18133 | Other | - | BCBS |
| 102170 | Other | - | CIGNA |
| 1550588404 | Other | - | CONNECTICARE |
| 3182916 | Medicaid | MA | - |
| 1204585 | Other | - | UNITED HEALTHCARE |
| 155058 | Other | - | TUFTS |
| 975887 | Other | - | NETWORK HEALTH |
| 010155058MA01 | Other | - | ANTHEM BCBS |
| 201928 | Other | - | HARVARD PILGRIM |
| 000000008141 | Other | - | BOSTON MED CENTER HEALTH |
What is an NPI number?
A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.
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Other providers at this practice address
Browse all →Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2023-03-07.