Quick answers
- Does Cassidy W. Claassen accept Medicare assignment?
- Yes. Medicare's clinician data says Cassidy W. Claassen 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 Cassidy W. Claassen see?
- In 2024, CMS data shows 11 Original Medicare patients and 37 services for Cassidy W. Claassen. This counts Original Medicare only and measures volume, not quality.
- What is Cassidy W. Claassen's NPI number?
- 1477796696. 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 Cassidy W. Claassen, 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 | 11 |
|---|---|
| Services billed to Medicare | 37 |
| Different services or procedures | 9 |
| Participating Medicare provider | Yes |
| Average age of these patients | 62 |
Hospitals where Cassidy W. Claassen works
Medicare's Facility Affiliation Data lists Cassidy W. Claassen 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.
- University of Maryland Medical CenterBaltimore, MD · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 210002
Practice locations
Addresses where Cassidy W. Claassen is enrolled with Medicare (CMS data updated October 2, 2026).
- 22 S Green StBaltimore, MD 21201 (410) 328‑8040
Group practices
Medicare enrollment lists Cassidy W. Claassen as a member of this group (CMS data updated October 2, 2026).
- University of Maryland Physicians PA404 clinicians in the group
Specialties
- Infectious Diseaseprimary
- Internal Medicinealso
Other infectious disease doctors in Baltimore
Clinicians with the same Medicare primary specialty in Baltimore, MD — not a recommendation.
Other clinicians in University of Maryland Physicians PA
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of Maryland School Of Medicine |
| Graduation year | 2009 (17 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1477796696 |
| 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