Dr. John Charles Gustafson, MD
- Medicare services, 2024
- 232
- Medicare patients, 2024
- 172
- Part D claims, 2024
- 516
- Hospital affiliations
- 1
- Industry payments
- $813
- Practice address
- 120 N Ashwood Ave, Ventura, CA 93003
- Practice phone
- Call (805) 948-5800
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Community Memorial Health System
Ventura, California
Find Dr. Gustafson's professional email, personal email and mobile number
Dmand AI checks each channel through healthcare-specific waterfall enrichment. See what is on file with a free account, with practice phones, licenses and affiliations.
Dr. John Charles Gustafson is an OB-GYN in Ventura, California
Dr. Gustafson practices at Community Memorial Health System in Ventura, California.
Dr. Gustafson's NPI, 1003836016, was assigned on July 20, 2006. Dr. Gustafson graduated from University of Rochester Medical Center in 1977. Dr. Gustafson's California license number on file is G36782.
- NPI
- 1003836016NPI Registry (opens in a new tab)
- Medicare PAC ID
- 9537106265
- NPI enumeration date
- July 20, 2006
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Practice phone
- (805) 948-5800
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Estimated age
- 75
- Medical school graduation
- 1977
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Practice Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. John Charles Gustafson practices at Community Memorial Health System in Ventura, California
Dr. Gustafson's primary practice is Community Memorial Health System, at 120 N Ashwood Ave, Ventura, CA 93003 in Ventura County. The practice phone is (805) 948-5800.
- Community Memorial Health System120 N Ashwood Ave, Ventura, CA 93003 · Ventura CountyPhone(805) 948-5800
Sources: NPPES NPI Registry (CMS); and Dmand AI Practice Data
Dr. John Charles Gustafson is affiliated with 4 sites of care and 2 medical groups
Dr. Gustafson's primary practice is Community Memorial Health System in Ventura, California. Dr. Gustafson is also affiliated with Community Memorial Hospital - Ventura. The medical group on file is Community Memorial Healthcare. Dmand AI also links Dr. Gustafson to 2 more group practices and clinics and 1 medical group, each named with a free account.
Sources: NPPES NPI Registry (CMS); Dmand AI Practice Data; and Dmand AI Affiliation Data
Dmand AI tracks the EHR system at Dr. John Charles Gustafson's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Gustafson practices, 3 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Community Memorial Health System | Available with a free account |
| +3 more sites and 1 medical group | Available with a free account |
Source: Dmand AI Technology Install Data
For health IT teams
Dmand AI maps EHR vendors, IT decision makers and buying committees across each health system and 6.2K+ hospitals, with verified contacts in the same login.
Dr. John Charles Gustafson is one of 4,642 OB-GYNs in California
Obstetrics and gynecology is Dr. Gustafson's primary specialty in the NPI Registry, under taxonomy code 207V00000X. Dr. Gustafson is board certified in obstetrics & gynecology by the American Board of Obstetrics and Gynecology. Dr. Gustafson has a license on file in California.
Specialties and state licenses
- Obstetrics and gynecology, CaliforniaPrimary
Clinical focus
Dmand AI lists hysterectomy, menopause, ovarian cyst, pelvic prolapse, UTI and vaginal infection among the conditions Dr. Gustafson treats.
OB-GYNs near Dr. Gustafson
Counts of OB-GYNs with a Dmand AI profile, by place and practice. Each opens the list.
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Dr. John Charles Gustafson billed Medicare for 232 services in 2024
CMS data shows 232 Medicare services from Dr. Gustafson across 5 procedure codes in 2024, for 172 Medicare patients. Medicare paid $13,203 for them.
Dr. Gustafson's Medicare services by type, 2023 to 2024
- 2023
- 2024
- Other services
- 2023: 1542024: 154No change
- Office and hospital visits
- 2023: 812024: 6717%
- Surgery
- 2023: 02024: 11
- Lab and pathology
- 2023: 182024: 0100%
Where Dr. Gustafson's Medicare services took place, 2024
- In an office22195%
- In a facility115%
Dr. Gustafson compared with the California median for OB-GYNs, 2024
- Dr. Gustafson
- California median
- Medicare services
- 232vs 584.0 times
- Medicare patients
- 172vs 523.3 times
- Part D claims
- 355vs 3510.1 times
Medians across 3,823 OB-GYNs in California with Dmand AI profiles that report each measure.
Dr. Gustafson's most billed Medicare procedure codes, 2024
CMS publishes codes billed for 11 or more Medicare patients. Each label is the code family; CPT descriptions are licensed by the AMA.
Need commercial claims for Dr. Gustafson?
Medicare shows one payer. Book a meeting to get commercial claims data for Dr. Gustafson and other OB-GYNs in California.
Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. John Charles Gustafson treated 172 Medicare patients in 2024, average age 71
CMS counts 172 Medicare patients who saw Dr. Gustafson in 2024. The largest group is 65 to 74, with 121 patients. 75% of them have high cholesterol, and 50% have high blood pressure. Their average risk score is 0.72, where 1.00 is the Medicare average.
Across all payers, Dmand AI patient panel data puts Dr. Gustafson's median patient age at 40, with 99% women.
Dr. Gustafson's Medicare patients by age, 2024
CMS leaves out age groups with fewer than 11 patients.
Chronic conditions among Dr. Gustafson's Medicare patients, 2024
- High cholesterol75%
- High blood pressure50%
- Arthritis47%
- Mood disorders29%
- Osteoporosis28%
- Depression27%
- Anxiety20%
- Cancer16%
Share of Medicare patients with each condition. A patient can have several.
Dr. Gustafson's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 40
Patient panel by sex, all payers
- Women99%
- Men0%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Dr. John Charles Gustafson wrote 516 Medicare Part D claims in 2024
In 2024, Dr. Gustafson wrote 516 Medicare Part D claims for 150 patients. 88% of them were for generic drugs. CMS names the drug for 355 of them, across 13 drugs with 11 or more claims each, at $22,934 in total drug cost. In 2023, CMS named 430 claims across 15 drugs.
Dr. Gustafson's Part D claims by kind of drug, 2024
- Generic453 claims88%
- Brand-name63 claims12%
Dr. Gustafson's most prescribed drugs by claims, 2024
CMS names a drug when it has 11 or more claims. Share is of the claims for drugs CMS names.
Part D claims for drugs CMS names, 2023 to 2024
- 2023
- 2024
- Claims for drugs CMS names
- 2023: 4302024: 35517%
Drugs named by CMS: 13 in 2024, 15 in 2023.
Sources: Medicare Part D Prescribers - by Provider and Drug (CMS), 2024 data, released May 6, 2026; and Medicare Part D Prescribers - by Provider (CMS), 2024 data
How Dr. John Charles Gustafson takes part in Medicare
Dr. Gustafson accepts Medicare assignment, so Medicare's approved amount is taken as full payment.
- Accepts Medicare assignment
- Yes
Source: Doctors and Clinicians National Downloadable File (CMS)
For MedTech and pharma teams
Filter 7.4M+ HCPs by Medicare procedures, Part D drugs and Open Payments history, then reach them with verified contacts in one login.
Dr. John Charles Gustafson received $813 in industry payments from 2017 to 2025
CMS Open Payments shows 138 general payments to Dr. Gustafson from 19 drug and device companies from 2017 to 2025. Food and beverage make up the largest share, 86% of the total. Shionogi Inc paid the most, $126.
General payments to Dr. Gustafson by program year, 2017 to 2025
General payments to Dr. Gustafson by kind, 2017 to 2025
- Food and beverage$69786%
- Gifts$11614%
Companies that paid Dr. Gustafson the most, 2017 to 2025
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. John Charles Gustafson has 3 awards and honors on record
Dmand AI lists 3 awards for Dr. Gustafson, most recently Top Doctors:LA Area in 2013.
Awards and honors for Dr. Gustafson
- 2013
- Top Doctors:LA Area
- 2012
- Top Doctors:Southern California
- Undated
- ACOG Fellow
Source: Dmand AI Professional Profile Data
Dr. John Charles Gustafson graduated from University of Rochester Medical Center
Dr. Gustafson graduated from University of Rochester Medical Center in 1977. Dr. Gustafson is a member of American College of Obstetricians and Gynecologists.
- Medical school
- Board certified in obstetrics & gynecology
Source: Dmand AI Professional Profile Data
Dr. John Charles Gustafson accepts plans from 15 insurance carriers
Dr. Gustafson is in network with 15 carriers, including Aetna, Elevance and Blue Cross Blue Shield of Michigan. PPO plans come from the most carriers, 10. Check the plan with the practice before a visit.
- Aetna
- Elevance
- Blue Cross Blue Shield of Michigan
- United Healthcare
- HCSC
- Humana
- Blue Cross Blue Shield of Massachusetts
- Regence Health Plans
- +7 more carriersWith a free account
Plan types Dr. Gustafson accepts, by number of carriers
- PPO10
- Medicare9
- HMO7
- POS5
- EPO4
Source: Dmand AI Insurance Network Data
Sources for Dr. John Charles Gustafson's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice Data |
| Primary practice, affiliations and health system | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice DataDmand AI Affiliation Data |
| Medicare services and procedure codes | Medicare Physician & Other Practitioners - by Provider and Service (CMS) (opens in a new tab) |
| State medians for the same specialty | Dmand AI Peer Benchmarks |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel DataMedicare Physician & Other Practitioners - by Provider (CMS) (opens in a new tab) |
| Part D prescribing | Medicare Part D Prescribers - by Provider and Drug (CMS) (opens in a new tab)Medicare Part D Prescribers - by Provider (CMS) (opens in a new tab) |
| MIPS scores, telehealth, assignment and procedure percentiles | Doctors and Clinicians National Downloadable File (CMS) (opens in a new tab) |
| Industry payments | Open Payments (CMS) (opens in a new tab) |
| Awards and committee roles | Dmand AI Professional Profile Data |
| Training, board certification and memberships | Dmand AI Professional Profile Data |
| Insurance carriers and plan types | Dmand AI Insurance Network Data |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Dr. John Charles Gustafson
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Dr. John Charles Gustafson's NPI number?
Dr. John Charles Gustafson's NPI number is 1003836016. It was assigned on July 20, 2006, and it is active in the NPI Registry.
What kind of doctor is Dr. John Charles Gustafson?
Dr. John Charles Gustafson is an OB-GYN in Ventura, California. The primary specialty in the NPI Registry is Obstetrics & Gynecology Physician (taxonomy code 207V00000X).
Where does Dr. John Charles Gustafson practice?
Dr. Gustafson practices at 120 N Ashwood Ave, Ventura, CA 93003. Dr. Gustafson's primary practice is Community Memorial Health System in Ventura, California. Dmand AI also links Dr. Gustafson to 2 group practices and clinics and 1 medical group.
What is Dr. John Charles Gustafson's office phone number?
The practice phone on file for Dr. Gustafson is (805) 948-5800.
What is Dr. John Charles Gustafson's medical license number?
Dr. Gustafson's California license number on file is G36782.
Which hospitals is Dr. John Charles Gustafson affiliated with?
Dr. Gustafson is affiliated with Community Memorial Hospital - Ventura.
What medical group is Dr. John Charles Gustafson part of?
Dr. Gustafson is linked to Community Memorial Healthcare. Dmand AI links Dr. Gustafson to 1 more medical group.
Does Dr. John Charles Gustafson accept Medicare?
Yes. CMS data shows Dr. Gustafson billed Medicare for 232 services in 2024, and Dr. Gustafson accepts Medicare assignment.
How many Medicare patients does Dr. John Charles Gustafson see?
CMS counts 172 Medicare patients who saw Dr. Gustafson in 2024, with an average age of 71.
Is Dr. John Charles Gustafson board certified?
Yes. Dr. Gustafson is board certified in obstetrics & gynecology by the American Board of Obstetrics and Gynecology.
Show 6 more questionsShow fewer questions
What services does Dr. John Charles Gustafson bill to Medicare?
In 2024, Dr. Gustafson's most billed Medicare services were medicare service (G0101), office visit, established patient (99213) and medicare temporary code (Q0091).
Where did Dr. John Charles Gustafson go to medical school?
Dr. Gustafson graduated from University of Rochester Medical Center in 1977.
What drugs does Dr. John Charles Gustafson prescribe most?
In 2024 Medicare Part D data, Dr. Gustafson's most prescribed drugs by claims were Estradiol, Progesterone and Estradiol (Twice Weekly).
Has Dr. John Charles Gustafson received payments from drug or device companies?
CMS Open Payments shows $813 in general payments to Dr. Gustafson from 19 companies from 2017 to 2025. The largest total came from Shionogi Inc.
How long has Dr. John Charles Gustafson been practicing?
Dr. Gustafson graduated from medical school in 1977, 49 years ago.
What insurance does Dr. John Charles Gustafson accept?
Dr. Gustafson is in network with 15 carriers, including Aetna, Elevance and Blue Cross Blue Shield of Michigan. PPO plans come from the most carriers, 10. Check the plan with the practice before a visit.
Selling to obstetrics and gynecology practices?
See OB-GYNs in California by site of care and group
Find the practices, groups and hospitals they work with, and the right people to contact at each.
- 30 days free
- Self-serve
- No credit card