Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum
Dr. Rosemarie Dieffenbach, MD
Pediatrics Physician in Weston, MA · enumerated 2007.
Data current as of Jul 13, 2026 · sourced from CMS NPPES
National Provider Identifier
1144344318
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Registry record
Entity type Individual (Type 1)
Name Dr. Rosemarie Dieffenbach
Credential MD
Sex Female
Practice address 486 Boston Post Road, Weston, MA, 02493
Phone (781) 899-4456
Fax (781) 647-9578
Enumeration date Mar 16, 2007
Last updated in NPPES Jan 13, 2012
Taxonomy & licenses
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure.
About the MD credential
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.
Frequently asked questions
What is the NPI number for Rosemarie Dieffenbach?
The National Provider Identifier (NPI) for Rosemarie Dieffenbach is 1144344318, a Type 1 (individual) record in the CMS NPPES registry.
Where does Rosemarie Dieffenbach practice?
The practice location on file with NPPES is in Weston, MA. Providers can have multiple locations; NPPES lists the primary practice address.
Other providers at this practice address
Browse all → Shelly Bernstein Pediatrics Physician · Weston, MA NPI 1457395980 Joshua Gundersheimer Pediatrics Physician · Weston, MA NPI 1790718757 Colleen Brownell-Krupat Pediatrics Physician · Weston, MA NPI 1841201993 Karen Ashworth Family Nurse Practitioner · Weston, MA NPI 1336276898 Katherine Bui Pediatrics Physician · Weston, MA NPI 1659530285
Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2012-01-13.