Quick answers
- Does Brent J. Geffen accept Medicare assignment?
- Yes. Medicare's clinician data says Brent J. Geffen 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 Brent J. Geffen see?
- In 2024, CMS data shows 721 Original Medicare patients and 1,791 services for Brent J. Geffen. This counts Original Medicare only and measures volume, not quality.
- What is Brent J. Geffen's NPI number?
- 1528562527. 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 Brent J. Geffen, 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 | 721 |
|---|---|
| Services billed to Medicare | 1,791 |
| Different services or procedures | 69 |
| Participating Medicare provider | Yes |
| Average age of these patients | 77 |
Most frequent services
- Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)384 services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)263 services
- Removal of impacted ear wax (69210)260 services
- New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more (99203)235 services
- New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more (99204)129 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%
- Arthritis58%
- Ischemic heart disease36%
- Diabetes27%
- Chronic kidney disease24%
Hospitals where Brent J. Geffen works
Medicare's Facility Affiliation Data lists Brent J. Geffen 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.
- Los Robles Hospital & Medical CenterThousand Oaks, CA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 050549
- St Johns Regional Medical CenterOxnard, CA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 050082
Practice locations
Addresses where Brent J. Geffen is enrolled with Medicare (CMS data updated October 2, 2026).
- 2415 E Main StVentura, CA 93003 (805) 454‑7133
- 2438 N Ponderosa Dr, Suite C110Camarillo, CA 93010 (805) 484‑5929
- 2876 Sycamore Dr, Suite 303Simi Valley, CA 93065 (805) 527‑7320
- 299 W Hillcrest Dr, Suite 100Thousand Oaks, CA 91360 (805) 379‑9646
- 301 S Moorpark RdThousand Oaks, CA 91361 (805) 379‑9646
Group practices
Medicare enrollment lists Brent J. Geffen as a member of these groups (CMS data updated October 2, 2026).
- Bass Medical Group291 clinicians in the group
- West Coast Ear, Nose and Throat7 clinicians in the group
Specialties
- Otolaryngologyprimary
Other ENT doctors in Ventura
Clinicians with the same Medicare primary specialty in Ventura, CA — not a recommendation.
Other clinicians in Bass Medical Group
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Wake Forest University School Of Medicine |
| Graduation year | 2018 (8 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1528562527 |
| 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