John Gustafson, M.D.
NPI 1003836016 · Obstetrics & Gynecology Physician · Ventura, CA
Enrolled with Medicare as Practitioner - Obstetrics/Gynecology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
John Gustafson, M.D. is a Obstetrics & Gynecology Physician provider in Ventura, CA (NPI 1003836016).
Provider details
- NPI number
- 1003836016
- Entity type
- Individual
- Primary specialty
- Obstetrics & Gynecology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- G36782 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
19 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
232 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Cervical Or Vaginal Cancer Screening; Pelvic and Clinical Breast ExaminationG0101 | 111 | $42 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 54 | $97 |
| Screening Papanicolaou Smear; Obtaining, Preparing and Conveyance of Cervical Or Vaginal Smear to LaboratoryQ0091 | 43 | $49 |
| New Patient Office Or Other Outpatient Visit With Low Level of Medical Decision Making, If Using Time, 30 Minutes Or More99203 | 13 | $119 |
| Biopsy of Lining of Uterus And/Or Removal of Polyp Using an Endoscope58558 | 11 | $233 |
Typical Medicare-allowed amounts for these services range $42–$233 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 13 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Estradiol | 132 | 55 |
| Progesterone, Micronizedbrand: Progesterone | 43 | 18 |
| Estradiolbrand: Estradiol (twice Weekly) | 36 | 11 |
| Clotrimazole/Betamethasone Dipbrand: Clotrimazole-Betamethasone | 22 | — |
| Estradiol/Norethindrone Acetbrand: Estradiol-Norethindrone Acetat | 17 | — |
| Valacyclovir Hclbrand: Valacyclovir | 17 | — |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$54 across 3 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-07-20
- Last updated
- 2007-07-09
Frequently asked questions
- What is John Gustafson's NPI number?
- John Gustafson's National Provider Identifier (NPI) is 1003836016, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is John Gustafson's specialty?
- John Gustafson is listed in the NPPES registry with a primary specialty of Obstetrics & Gynecology Physician (Allopathic & Osteopathic Physicians).
- Where is John Gustafson located?
- John Gustafson's practice location on file with NPPES is 2795 Loma Vista Rd, Ventura, CA 93003-1544.
- What is John Gustafson's phone number?
- The practice phone number listed in the NPPES registry for John Gustafson is (805) 643-8695.
- Does John Gustafson accept Medicare?
- John Gustafson is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is John Gustafson's NPI active?
- Yes — John Gustafson's NPI (1003836016) is active in the NPPES registry as of the last update on 2007-07-09.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.