Quick answers
- Does Sarah S. Nielsen accept Medicare assignment?
- Yes. Medicare's clinician data says Sarah S. Nielsen 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 Sarah S. Nielsen see?
- In 2024, CMS data shows 1,594 Original Medicare patients and 5,549 services for Sarah S. Nielsen. This counts Original Medicare only and measures volume, not quality.
- What is Sarah S. Nielsen's NPI number?
- 1134137995. 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 Sarah S. Nielsen, 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 | 1,594 |
|---|---|
| Services billed to Medicare | 5,549 |
| Different services or procedures | 33 |
| Participating Medicare provider | Yes |
| Average age of these patients | 72 |
Most frequent services
- Screening mammography (77067)2,310 services
- Screening 3d breast mammography (77063)2,262 services
- Diagnostic digital breast tomosynthesis, unilateral or bilateral (list separately in addition to 77065 or 77066) (G0279)155 services
- Limited ultrasound scan of 1 breast (76642)110 services
- Diagnostic mammography of 1 breast (77065)94 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 cholesterol68%
- High blood pressure62%
- Arthritis34%
- Anxiety22%
- Osteoporosis22%
- Diabetes21%
Hospitals where Sarah S. Nielsen works
Medicare's Facility Affiliation Data lists Sarah S. Nielsen 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.
- Flambeau HospitalPark Falls, WI · Critical Access Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 521325
- Marshfield Medical Center - LadysmithLadysmith, WI · Critical Access Hospital · Emergency services: listed by Medicare · CCN 521328
- Marshfield Medical Center - MinocquaMinocqua, WI · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 520212
- Marshfield Medical Center - Rice LakeRice Lake, WI · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 520011
- Marshfield Medical Center - WestonWeston, WI · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 520202
Practice locations
Addresses where Sarah S. Nielsen is enrolled with Medicare (CMS data updated October 2, 2026). The first 5 of 6; the Medicare profile lists all.
- 1000 N Oak AveMarshfield, WI 54449 (715) 387‑5511
- 2655 County Hwy IChippewa Falls, WI 54729 (715) 726‑4200
- 2727 Plaza DrWausau, WI 54401 (715) 847‑3000
- 3400 Ministry PkwyWeston, WI 54476 (715) 393‑3000
- 3400 Ministry Pkwy, Suite 5Weston, WI 54476 (715) 393‑0080
Group practices
Medicare enrollment lists Sarah S. Nielsen as a member of these groups (CMS data updated October 2, 2026).
- MCHS Hospitals Inc1,197 clinicians in the group
- Marshfield Clinic Inc207 clinicians in the group
Specialties
- Diagnostic Radiologyprimary
Other radiologists in Marshfield
Clinicians with the same Medicare primary specialty in Marshfield, WI — not a recommendation.
Other clinicians in MCHS Hospitals Inc
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | DO |
|---|---|
| Medical school | Michigan State University College Of Osteopathic Medicine |
| Graduation year | 2000 (26 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1134137995 |
| 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