Quick answers
- Does Karen A. Vanleuven accept Medicare assignment?
- Yes. Medicare's clinician data says Karen A. Vanleuven 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 Karen A. Vanleuven see?
- In 2024, CMS data shows 440 Original Medicare patients and 2,034 services for Karen A. Vanleuven. This counts Original Medicare only and measures volume, not quality.
- What is Karen A. Vanleuven's NPI number?
- 1003967415. 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 Karen A. Vanleuven, 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 | 440 |
|---|---|
| Services billed to Medicare | 2,034 |
| Different services or procedures | 11 |
| Participating Medicare provider | Yes |
| Average age of these patients | 78 |
Most frequent services
- Subsequent nursing facility care with moderate level of medical decision making, per day, if using time, at least 30 minutes (99309)1,425 services
- Subsequent nursing facility care with straightforward level of medical decision making, per day, if using time, 20 minutes or more (99308)267 services
- Nursing facility discharge management, more than 30 minutes (99316)123 services
- Residence visit for established patient with moderate level of medical decision making, per day, if using time, at least 40 minutes (99349)86 services
- Advance care planning, first 30 minutes (99497)53 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 cholesterol72%
- Arthritis45%
- Chronic kidney disease44%
- Diabetes43%
- Depression40%
Practice locations
Addresses where Karen A. Vanleuven is enrolled with Medicare (CMS data updated October 2, 2026).
- 1255 Travis BlvdFairfield, CA 94533 (800) 973‑1540
Group practices
Medicare enrollment lists Karen A. Vanleuven as a member of this group (CMS data updated October 2, 2026).
- SNF Specialists Medical Corporation28 clinicians in the group
Specialties
- Nurse Practitionerprimary
Other nurse practitioners in Fairfield
Clinicians with the same Medicare primary specialty in Fairfield, CA — not a recommendation.
Other clinicians in SNF Specialists Medical Corporation
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | NP |
|---|---|
| Graduation year | 1999 |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1003967415 |
| 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
- 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