James Diener, D.O.
NPI 1588004915 · Internal Medicine Physician · Cadillac, MI
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
James Diener, D.O. is a Internal Medicine Physician provider in Cadillac, MI (NPI 1588004915).
Provider details
- NPI number
- 1588004915
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- D.O.
- Sex
- Male
- Sole proprietor
- Yes
- License
- 5101020738 (MI)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure33% of score
13 yrs in NPPES registry
- Profile completeness33% of score
100% of core fields populated
- Practice footprint20% of score
2 documented practice locations
- Open Payments transparency13% of score
Has Open Payments disclosures (2024)
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.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 161 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 644 | 162 |
| Gabapentin | 374 | 66 |
| Lisinopril | 349 | 95 |
| Levothyroxine Sodium | 340 | 88 |
| Amlodipine Besylate | 317 | 88 |
| Omeprazole | 313 | 80 |
| Losartan Potassium |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$116 across 6 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Additional practice locations (1)
- 100 N Roland StMc Bain, MI 49657-9683Phone: (231) 825-8101Fax: (231) 825-8104
Registry dates
- Enumerated
- 2013-06-29
- Last updated
- 2020-11-23
- Certified
- 2020-11-23
Frequently asked questions
- What is James Diener's NPI number?
- James Diener's National Provider Identifier (NPI) is 1588004915, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is James Diener's specialty?
- James Diener is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is James Diener located?
- James Diener's practice location on file with NPPES is 7985 S Mackinaw Trl, Cadillac, MI 49601-8111.
- What is James Diener's phone number?
- The practice phone number listed in the NPPES registry for James Diener is (231) 779-0320.
- Does James Diener accept Medicare?
- James Diener is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is James Diener's NPI active?
- Yes — James Diener's NPI (1588004915) is active in the NPPES registry as of the last update on 2020-11-23.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.