Clay Hughes Napper, M.D.
Diagnostic Radiology Physician · San Mateo, CA
Clay Hughes Napper, M.D. is a diagnostic radiology physician with a practice address in San Mateo, California, and NPI 1053352815, issued on Jun 10, 2006. Check the license (California G78045, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Clay Hughes Napper
- Credential
- M.D.
- Primary taxonomy
- Diagnostic Radiology Physician 2085R0202X
- License number
- G78045 CA
Self-reported in NPPES; status is on the state search - Practice location
- 100 S San Mateo Dr, San Mateo, CA 94401
- Phone
- (650) 696-4515
- Enumerated
- Jun 10, 2006
- Record last updated
- Mar 19, 2021 (not updated in 5 years: call before relying on the address or phone)
- Fax
- (650) 696-4626
- Medicaid ID
- 00G780450 CA
- Medicare enrollment
- Enrolled (PECOS I20080627000143); accepts Medicare assignment
- Medical or professional school
- Wake Forest University School Of Medicine, 1992
- Entity
- Type 1 · individual
8 nearest diagnostic radiology physician records → All 4,500 in California → Look up another NPI →
Also registered at 100 S San Mateo Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Frederick Adler, M.D.Family Medicine Physician1629030515
- Avanti Ambekar, M.D.Diagnostic Radiology Physician1356447627
- Mandeep Bajwa, M.D.Family Medicine Physician1891083978
- Harriet Borofsky, M.D.Diagnostic Radiology Physician1033162912
- Kelly Broderick, M.D.Diagnostic Radiology Physician1609821891
- Joey CheungRadiological Physics Physician1154256493
Verify Clay Hughes Napper in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license G78045Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Bills Medicare through 3 group practices
- California Advanced Imaging Medical Associates IncSan Mateo, CA
- County OF San MateoSan Mateo, CA
- Sutter Bay Medical FoundationBurlingame, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Clay Hughes Napper among 4,500 diagnostic radiology physician records in California
Clay Hughes Napper, 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
- Graduated1992 · median 2004 among the 3,130 with a school on file
- Record last updated2021 · 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).
Diagnostic Radiology Physician providers in California
There are 4,500 diagnostic radiology physician records in California.
All 4,500 in California → Every provider in San Mateo → Diagnostic Radiology Physician nationwide →
The 8 diagnostic radiology physician records with the nearest ZIP codes
- Avanti Ambekar, M.D.San Mateo, CA 944011356447627
- Harriet Borofsky, M.D.San Mateo, CA 944011033162912
- Kelly Broderick, M.D.San Mateo, CA 944011609821891
- Doris Burton, MDSan Mateo, CA 944011285837906
- Rahi Kumar, M.D.San Mateo, CA 944011730452806
- Nancy Lai, M.D.San Mateo, CA 944011932326188
- Nicole Lee, MDSan Mateo, CA 944011669615183
- Kathleen McKenna, M.D.San Mateo, CA 944011699711358
Common questions
What is Clay Hughes Napper, M.D.'s NPI number?
Clay Hughes Napper, M.D.'s National Provider Identifier (NPI) is 1053352815, issued on Jun 10, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Clay Hughes Napper, M.D. located?
The NPPES record lists a practice address at 100 S San Mateo Dr, San Mateo, CA, 94401. Phone: (650) 696-4515. Providers update this record themselves, so call before visiting.
How can I verify Clay Hughes Napper, M.D.'s license?
NPPES lists California license number G78045, 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.
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.