Quick answers
- Does Carl W. Nissen accept Medicare assignment?
- Medicare's clinician data says Carl W. Nissen may accept Medicare assignment (as of October 2, 2026). Ask the office whether they accept it for your visit.
- How many Medicare patients does Carl W. Nissen see?
- In 2024, CMS data shows 26 Original Medicare patients and 42 services for Carl W. Nissen. This counts Original Medicare only and measures volume, not quality.
- What is Carl W. Nissen's NPI number?
- 1982601530. 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 Carl W. Nissen, 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 | 26 |
|---|---|
| Services billed to Medicare | 42 |
| Different services or procedures | 7 |
| Participating Medicare provider | Yes |
| Average age of these patients | 72 |
Most frequent services
- New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more (99203)12 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 cholesterol73%
- High blood pressure65%
- Arthritis58%
Hospitals where Carl W. Nissen works
Medicare's Facility Affiliation Data lists Carl W. Nissen 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.
- Hartford HospitalHartford, CT · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 070025
Practice locations
Addresses where Carl W. Nissen is enrolled with Medicare (CMS data updated October 2, 2026).
- 31 Seymour St, Fl 2Hartford, CT 06106 (860) 972‑0050
- 31 Seymour St, Suite 204Hartford, CT 06106 (860) 282‑0833
- 80 Seymour StHartford, CT 06102
Group practices
Medicare enrollment lists Carl W. Nissen as a member of this group (CMS data updated October 2, 2026).
- Hartford Hospital1,044 clinicians in the group
Specialties
- Sports Medicineprimary
- Orthopedic Surgeryalso
Other sports medicine doctors in Connecticut
Clinicians with the same Medicare primary specialty in Connecticut — not a recommendation.
Other clinicians in Hartford Hospital
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of Connecticut School Of Medicine |
| Graduation year | 1990 (36 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | May accept for some services |
| NPI (National Provider Identifier) | 1982601530 |
| 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