Frederick Dietz, MD
NPI 1235249426 · Rheumatology Physician · Rockford, IL
Enrolled with Medicare as Practitioner - Rheumatology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Frederick Dietz, MD is a Rheumatology Physician provider in Rockford, IL (NPI 1235249426).
Provider details
- NPI number
- 1235249426
- Entity type
- Individual
- Primary specialty
- Rheumatology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- 036-050026 (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
19 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
- 2006-08-30
- Last updated
- 2010-02-02
Frequently asked questions
- What is Frederick Dietz's NPI number?
- Frederick Dietz's National Provider Identifier (NPI) is 1235249426, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Frederick Dietz's specialty?
- Frederick Dietz is listed in the NPPES registry with a primary specialty of Rheumatology Physician (Allopathic & Osteopathic Physicians).
- Where is Frederick Dietz located?
- Frederick Dietz's practice location on file with NPPES is 2300 N Rockton Ave, Rockford, IL 61103-3619.
- What is Frederick Dietz's phone number?
- The practice phone number listed in the NPPES registry for Frederick Dietz is (815) 971-2000.
- Does Frederick Dietz accept Medicare?
- Frederick Dietz is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Frederick Dietz's NPI active?
- Yes — Frederick Dietz's NPI (1235249426) is active in the NPPES registry as of the last update on 2010-02-02.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.