Quick answers
- Does Joseph F. Jahner accept Medicare assignment?
- Yes. Medicare's clinician data says Joseph F. Jahner accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Joseph F. Jahner see?
- In 2024, CMS data shows 216 Original Medicare patients and 346 services for Joseph F. Jahner. This counts Original Medicare only and measures volume, not quality.
- What is Joseph F. Jahner's NPI number?
- 1285245274. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Joseph F. Jahner, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 216 |
|---|---|
| Services billed to Medicare | 346 |
| Different services or procedures | 14 |
| Participating Medicare provider | Yes |
| Average age of these patients | 75 |
Most frequent services
- Established patient complete exam of visual system (92014)184 services
- Photography of the retina (92250)53 services
- Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)26 services
- Imaging of optic nerve (92133)22 services
- Removal of cataract with insertion of prosthetic lens (66984)18 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High blood pressure70%
- High cholesterol64%
- Arthritis35%
- Diabetes29%
- Chronic kidney disease23%
- Ischemic heart disease16%
Practice locations
Addresses where Joseph F. Jahner is enrolled with Medicare (CMS data updated October 2, 2026).
- 935 Broad StGrinnell, IA 50112 (641) 236‑7502
Group practices
Medicare enrollment lists Joseph F. Jahner as a member of this group (CMS data updated October 2, 2026).
- Jensen Optometrists PLLC2 clinicians in the group
Specialties
- Optometryprimary
Other optometrists in Grinnell
Clinicians with the same Medicare primary specialty in Grinnell, IA — not a recommendation.
Other clinicians in Jensen Optometrists PLLC
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Graduation year | 2020 |
|---|---|
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1285245274 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians