John T. Armstrong, MD
Gynecology Physician · Napa, CA
John T. Armstrong, MD is a gynecology physician with a practice address in Napa, California, and NPI 1790875995, issued on Oct 16, 2006. Check the license (California 00C378990, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- John T. Armstrong
- Credential
- MD
- Primary taxonomy
- Gynecology Physician 207VG0400X
- License number
- 00C378990 CA
Self-reported in NPPES; status is on the state search - Practice location
- 3434 Villa LN, Napa, CA 94558
- Phone
- (707) 257-4317
- Enumerated
- Oct 16, 2006
- Record last updated
- Jul 8, 2007 (not updated in 19 years: call before relying on the address or phone)
- Fax
- (707) 257-4319
- Medicaid ID
- ZZR0009F CA
- Medicare enrollment
- Enrolled (PECOS I20080125000394); accepts Medicare assignment
- Medical or professional school
- Texas Tech University Health Science Center School Of Medicine, 1976
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest gynecology physician records → All 369 in California → Look up another NPI →
Also registered at 3434 Villa LN
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Kim Bellows, PAMedical Physician Assistant1114087145
- Robert Dunham, M.D.Surgery Physician1700851870
- Jacob Goldenberg, D.D.S.Periodontics1306974779
- Eric Grigsby, M.D.Pain Medicine Physician1952328494
- Thomas Johnson, D.M.D.General Practice Dentistry1750470688
- Cecil Lamberton, D.D.S.General Practice Dentistry1538384292
Verify John T. Armstrong in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 00C378990Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
2.2 times the Medicare Part D claims of the average gynecology physician in 2024
650 Medicare Part D claims for 139 beneficiaries, against an average of 299 among the 1,919 providers of this specialty who prescribed in Part D.
Most prescribed
- Estradiol257 claims
- Progesterone57 claims
- Terconazole39 claims
- Nitrofurantoin Mono-Macro36 claims
- Estradiol (Twice Weekly)24 claims
- Yuvafem23 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
No measured MIPS final score for 2023
CMS assigned the neutral MIPS final score of 75 without scoring Quality, Cost, Promoting Interoperability or Improvement Activities. It is an administrative threshold, so PlainDoctor does not compare it with measured clinicians.
Source: CMS Quality Payment Program, MIPS performance year 2023; category weights for 2023 (qpp.cms.gov).
Industry payments in 2024: $159.26
8 payments; by number, the most common kind was food and beverage; the largest payer was Radius Health, Inc. The 1,398 providers of this specialty with any payment received $2,469.88 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
John T. Armstrong among 369 gynecology physician records in California
John T. Armstrong, MD is one of 369 gynecology physician records with a practice address in California. 60% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 9% of them.
- NPI issued2006 · 9% of these records are older, 40% newer
- In a Medicare fileYes · 60% of these records are
- In the CMS Doctors and Clinicians fileYes · 38% of these records are
- Graduated1976 · median 1995 among the 141 with a school on file
- Record last updated2007 · 70% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207VG0400X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Gynecology Physician providers in California
There are 369 gynecology physician records in California.
All 369 in California → Every provider in Napa → Gynecology Physician nationwide →
The 8 gynecology physician records with the nearest ZIP codes
- Lovera Miller, M.D.Napa, CA 945581639252745
- Karen Kashkin, MDLafayette, CA 945491548225105
- Leah Millheiser, MDDublin, CA 945681023188331
- Sidney Wanetick, MDCastro Valley, CA 945461508869868
- Minjing WangHayward, CA 945451659246031
- Michael Miller, MDHayward, CA 945411861576043
- Catherine Behrens, MDFremont, CA 945381508831629
- Xiufen Ding, MDFremont, CA 945381528143203
Common questions
What is John T. Armstrong, MD's NPI number?
John T. Armstrong, MD's National Provider Identifier (NPI) is 1790875995, issued on Oct 16, 2006. An NPI identifies a provider in billing; it is not a license.
Where is John T. Armstrong, MD located?
The NPPES record lists a practice address at 3434 Villa LN, Napa, CA, 94558. Phone: (707) 257-4317. Providers update this record themselves, so call before visiting.
How can I verify John T. Armstrong, MD's license?
NPPES lists California license number 00C378990, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does John T. Armstrong, MD prescribe under Medicare Part D?
In 2024, John T. Armstrong, MD had 650 Medicare Part D claims for 139 beneficiaries; the average among gynecology physician prescribers was 299. Part D covers Medicare prescriptions only.
What is John T. Armstrong, MD's MIPS final score?
CMS assigned the neutral MIPS final score of 75 for 2023 without scoring any category, so it is not a measured result.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.