Quick answers
- Does Katherine C. Riordan accept Medicare assignment?
- Yes. Medicare's clinician data says Katherine C. Riordan 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 Katherine C. Riordan see?
- In 2024, CMS data shows 295 Original Medicare patients and 303 services for Katherine C. Riordan. This counts Original Medicare only and measures volume, not quality.
- What is Katherine C. Riordan's NPI number?
- 1689832107. 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 Katherine C. Riordan, 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 | 295 |
|---|---|
| Services billed to Medicare | 303 |
| Different services or procedures | 18 |
| Participating Medicare provider | Yes |
| Average age of these patients | 78 |
Most frequent services
- Telehealth consultation, critical care, initial , physicians typically spend 60 minutes communicating with the patient and providers via telehealth (G0508)116 services
- Telehealth consultation, emergency department or initial inpatient, typically 30 minutes communicating with the patient via telehealth (G0425)97 services
- Telehealth consultation, emergency department or initial inpatient, typically 50 minutes communicating with the patient via telehealth (G0426)17 services
- Measurement of brain wave activity (eeg), awake and asleep (95819)15 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%
- Stroke or mini-stroke75%
- Arthritis56%
- Ischemic heart disease54%
- Diabetes48%
Hospitals where Katherine C. Riordan works
Medicare's Facility Affiliation Data lists Katherine C. Riordan 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.
- AdventHealth OrlandoOrlando, FL · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 100007
- CHI Health Bergan MercyOmaha, NE · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 280060
- CHRISTUS St Michael Health SystemTexarkana, TX · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 450801
- McLeod Regional Medical Center-Pee DeeFlorence, SC · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 420051
- St Josephs HospitalTampa, FL · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 100075
Practice locations
Addresses where Katherine C. Riordan is enrolled with Medicare (CMS data updated October 2, 2026). The first 5 of 23; the Medicare profile lists all.
- 1000 Montauk HwyWest Islip, NY 11795 · Good Samaritan Hospital Medical Center (631) 376‑3000
- 1000 N Village AveRockville Center, NY 11570 · Mercy Medical Center (516) 705‑3428
- 1101 26th St SGreat Falls, MT 59405 · Benefis Hospitals Inc (406) 455‑5000
- 11190 Health Park BlvdNaples, FL 34110 (239) 552‑7000
- 1138 Country Club BlvdCape Coral, FL 33990 (239) 424‑1900
Group practices
Medicare enrollment lists Katherine C. Riordan as a member of these groups (CMS data updated October 2, 2026).
- Baptist Health Medical Group Inc2,472 clinicians in the group
- Lee Health System Inc1,428 clinicians in the group
- Altru Health System684 clinicians in the group
- Concord Hospital Inc567 clinicians in the group
- NCHMD Inc510 clinicians in the group
- Piedmont Hospitalist Physicians LLC508 clinicians in the group
Specialties
- Neurologyprimary
Other neurologists in West Islip
Clinicians with the same Medicare primary specialty in West Islip, NY — not a recommendation.
Other clinicians in Baptist Health Medical Group Inc
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 2008 (18 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1689832107 |
| 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