Quick answers
- Does Nels C. Gunnarsen accept Medicare assignment?
- Yes. Medicare's clinician data says Nels C. Gunnarsen 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 Nels C. Gunnarsen see?
- In 2024, CMS data shows 300 Original Medicare patients and 636 services for Nels C. Gunnarsen. This counts Original Medicare only and measures volume, not quality.
- What is Nels C. Gunnarsen's NPI number?
- 1821193160. 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 Nels C. Gunnarsen, 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 | 300 |
|---|---|
| Services billed to Medicare | 636 |
| Different services or procedures | 17 |
| Participating Medicare provider | Yes |
| Average age of these patients | 73 |
Most frequent services
- Screening 3d breast mammography (77063)116 services
- Screening mammography (77067)116 services
- Diagnostic digital breast tomosynthesis, unilateral or bilateral (list separately in addition to 77065 or 77066) (G0279)114 services
- Limited ultrasound scan of 1 breast (76642)89 services
- Diagnostic mammography of 1 breast (77065)82 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 cholesterol75%
- High blood pressure65%
- Arthritis49%
- Anxiety32%
- Osteoporosis32%
- Cancer (breast, colorectal, lung, prostate, endometrial or leukemia/lymphoma)31%
Hospitals where Nels C. Gunnarsen works
Medicare's Facility Affiliation Data lists Nels C. Gunnarsen at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- MercyOne Oelwein Medical CenterOelwein, IA · Critical Access Hospital · Emergency services: listed by Medicare · CCN 161338
- MercyOne Waterloo Medical CenterWaterloo, IA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 160067
- Sartori Memorial Hospital, IncCedar Falls, IA · Acute Care Hospital · Emergency services: listed by Medicare · CCN 160040
Practice locations
Addresses where Nels C. Gunnarsen is enrolled with Medicare (CMS data updated October 2, 2026).
- 100 N Academy AveDanville, PA 17822 (570) 271‑6541
Group practices
Medicare enrollment lists Nels C. Gunnarsen as a member of these groups (CMS data updated October 2, 2026).
- Geisinger Clinic3,467 clinicians in the group
- Lucidsolutions Inc61 clinicians in the group
Specialties
- Diagnostic Radiologyprimary
Other radiologists in Danville
Clinicians with the same Medicare primary specialty in Danville, PA — not a recommendation.
Other clinicians in Geisinger Clinic
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1990 (36 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1821193160 |
| 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
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- 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