William James Demartini, M.D.
Diagnostic Radiology Physician · Greenbrae, CA
William James Demartini, M.D. is a diagnostic radiology physician with a practice address in Greenbrae, California, and NPI 1427091016, issued on Jun 13, 2006. Check the license (California G27905, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- William James Demartini
- Credential
- M.D.
- Primary taxonomy
- Diagnostic Radiology Physician 2085R0202X
- License number
- G27905 CA
Self-reported in NPPES; status is on the state search - Practice location
- 250 Bon Air RD, Greenbrae, CA 94904
- Phone
- (415) 925-7301
- Enumerated
- Jun 13, 2006
- Record last updated
- Apr 26, 2010 (not updated in 16 years: call before relying on the address or phone)
- Medicaid ID
- 00G279050 CA
- Medicare enrollment
- Enrolled (PECOS I20060209000228); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest diagnostic radiology physician records → All 4,500 in California → Look up another NPI →
Also registered at 250 Bon Air RD
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Lisa Abrahams, MFTMarriage & Family Therapist1184738445
- Jory Adam, PA-CSurgical Physician Assistant1922269521
- Samuel Adams, MDHospitalist Physician1497785034
- Barbara Addleman, RNRegistered Nurse1053551267
- Linda Alexander, RNPsychiatric/Mental Health Registered Nurse1205589405
- Maxwell AlikinneyCounselor1538668728
Verify William James Demartini in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license G27905Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
The practice group's MIPS final score for 2023 (Medicare payment program): 85.7 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).
Bills Medicare through one group practice
- California Advanced Imaging Medical Associates IncSonoma, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
William James Demartini among 4,500 diagnostic radiology physician records in California
William James Demartini, M.D. is one of 4,500 diagnostic radiology physician records with a practice address in California. 74% 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 7% of them.
- NPI issued2006 · 7% of these records are older, 52% newer
- In a Medicare fileYes · 74% of these records are
- In the CMS Doctors and Clinicians fileYes · 70% of these records are
- Graduated1973 · median 2004 among the 3,130 with a school on file
- Record last updated2010 · 60% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 2085R0202X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
13 diagnostic radiology physician records list a practice address in Greenbrae
They are 13 of the 727 NPPES records with a practice address in Greenbrae, and 4,500 diagnostic radiology physician records in California.
All 4,500 in California → Every provider in Greenbrae → Diagnostic Radiology Physician nationwide →
The 8 diagnostic radiology physician records with the nearest ZIP codes
- Russell Fritz, M.D.Greenbrae, CA 949041679550032
- Chad Goodman, M.D.Greenbrae, CA 949041386686525
- Susan Gootnick, M.D.Kentfield, CA 949041386714905
- Donna Hoghooghi, M.D.Greenbrae, CA 949041295781201
- Betsy Holland, M.D.Greenbrae, CA 949041659357481
- Jay Kaiser, M.D.Greenbrae, CA 949041275519001
- Ralph Koenker, M.D.Greenbrae, CA 949041891734265
- Philip Kurzman, M.D.Greenbrae, CA 949041346424991
Common questions
What is William James Demartini, M.D.'s NPI number?
William James Demartini, M.D.'s National Provider Identifier (NPI) is 1427091016, issued on Jun 13, 2006. An NPI identifies a provider in billing; it is not a license.
Where is William James Demartini, M.D. located?
The NPPES record lists a practice address at 250 Bon Air RD, Greenbrae, CA, 94904. Phone: (415) 925-7301. Providers update this record themselves, so call before visiting.
How can I verify William James Demartini, M.D.'s license?
NPPES lists California license number G27905, 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.
What is William James Demartini, M.D.'s MIPS final score?
The 2023 MIPS final score is 85.7 of 100, reported for the practice group. The average among 454,083 clinicians with a measured score was 83.5.
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.