Quick answers
- Does Gregory A. Anderson accept Medicare assignment?
- Yes. Medicare's clinician data says Gregory A. Anderson 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 Gregory A. Anderson see?
- In 2024, CMS data shows 185 Original Medicare patients and 423 services for Gregory A. Anderson. This counts Original Medicare only and measures volume, not quality.
- What is Gregory A. Anderson's NPI number?
- 1134234610. 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 Gregory A. Anderson, 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 | 185 |
|---|---|
| Services billed to Medicare | 423 |
| Different services or procedures | 57 |
| Participating Medicare provider | Yes |
| Average age of these patients | 73 |
Most frequent services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)99 services
- Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)65 services
- Diagnostic exam of bladder and urethra using an endoscope (52000)46 services
- Insertion of stent in ureter using an endoscope (52332)33 services
- Established patient office or other outpatient visit with straightforward medical decision making, if using time, 10 minutes or more (99212)32 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 pressure75%
- High cholesterol75%
- Cancer (breast, colorectal, lung, prostate, endometrial or leukemia/lymphoma)46%
- Chronic kidney disease35%
- Arthritis34%
- Diabetes31%
Hospitals where Gregory A. Anderson works
Medicare's Facility Affiliation Data lists Gregory A. Anderson 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.
- Marshfield Medical CenterMarshfield, WI · Acute Care Hospital · Medicare rating: 1 of 5 stars · Emergency services: listed by Medicare · CCN 520037
- 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 - NeillsvilleNeillsville, WI · Critical Access Hospital · Emergency services: listed by Medicare · CCN 521323
- 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 Gregory A. Anderson is enrolled with Medicare (CMS data updated October 2, 2026).
- 1000 N Oak AveMarshfield, WI 54449 (715) 387‑5511
Group practices
Medicare enrollment lists Gregory A. Anderson as a member of this group (CMS data updated October 2, 2026).
- MCHS Hospitals Inc1,197 clinicians in the group
Specialties
- Urologyprimary
Other urologists 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 | MD |
|---|---|
| Medical school | University Of Wisconsin School Of Medicine |
| Graduation year | 1988 (38 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1134234610 |
| 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