Quick answers
- Does Karen S. Kiefer accept Medicare assignment?
- Yes. Medicare's clinician data says Karen S. Kiefer 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.
- What is Karen S. Kiefer's NPI number?
- 1578586574. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Practice locations
Addresses where Karen S. Kiefer is enrolled with Medicare (CMS data updated October 2, 2026).
- 1715 Leaning Pine DrDiamond Bar, CA 91765 (909) 261‑4123
Specialties
- Psychiatryprimary
Other psychiatrists in Diamond Bar
Clinicians with the same Medicare primary specialty in Diamond Bar, CA — not a recommendation.
Clinician information
| Credential | DO |
|---|---|
| Medical school | Midwestern University, Chicago College Of Osteopathic Med |
| Graduation year | 1976 (50 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1578586574 |
| 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
- 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