NPPES file of Aug 9, 2026

Margaret Riordan, MD

Neurological Surgery Physician · San Francisco, CA

Margaret Riordan, MD is a neurological surgery physician with a practice address in San Francisco, California, and NPI 1902061955, issued on Jul 18, 2008. Check the license (California 137141, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2023 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1902061955
Name
Margaret Riordan
Credential
MD
Primary taxonomy
Neurological Surgery Physician 207T00000X
License numbers
137141 CA
MD458962 PA
Self-reported in NPPES; status is on the state search
Practice location
400 Parnassus Ave, San Francisco, CA 94143
Phone
(415) 472-1000
Enumerated
Jul 18, 2008
Record last updated
Mar 17, 2018 (not updated in 8 years: call before relying on the address or phone)
Medicare enrollment
Enrolled (PECOS I20161104000057); accepts Medicare assignment
Medical or professional school
University Of Iowa, Rj & L Carver College Of Medicine, 2008
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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Also registered at 400 Parnassus Ave

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Jessica Abele, DPTPhysical Therapist1851648133
  2. Ian Adatia, MB CHBPediatric Cardiology Physician1427085299
  3. Daniel Adelman, M.D.Internal Medicine Physician1922041821
  4. Joshua Adler, MDInternal Medicine Physician1194781351
  5. Justin Ahn, M.D.Urology Physician1063755148
  6. Weiyun Ai, MDMedical Oncology Physician1649346842

Verify Margaret Riordan in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license 137141
    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Open the California license search

PlainDoctor does not match the HHS-OIG exclusion list to individual records: most entries carry no NPI. Search the OIG exclusion list by name.

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The practice group's MIPS final score for 2023 (Medicare payment program): 91 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.

  1. Qualityout of 100 · 30% of the final score82.1
  2. Costout of 100 · 30%64.1
  3. Promoting interoperabilityout of 100 · 25%100.0
  4. Improvement activities40 of 40 points · 15%100.0

Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).

Bills Medicare through one group practice

  1. Alameda Health SystemOakland, CA

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

Margaret Riordan among 929 neurological surgery physician records in California

Margaret Riordan, MD is one of 929 neurological surgery physician records with a practice address in California. 77% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2008, is newer than 52% of them.

  • NPI issued2008 · 52% of these records are older, 41% newer
  • In a Medicare fileYes · 77% of these records are
  • In the CMS Doctors and Clinicians fileYes · 66% of these records are
  • Graduated2008 · median 2005 among the 612 with a school on file
  • Record last updated2018 · 55% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207T00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

Neurological Surgery Physician providers in California

There are 929 neurological surgery physician records in California.

The 8 neurological surgery physician records with the nearest ZIP codes

  1. Manish Aghi, MD PHDSan Francisco, CA 941431689647778
  2. Christopher Ames, MDSan Francisco, CA 941431265485155
  3. Mitchel Berger, MDSan Francisco, CA 941431538117981
  4. Nicholas Butowski, MDSan Francisco, CA 941431184681009
  5. Susan Chang, MDSan Francisco, CA 941431346299518
  6. Nalin Gupta, MDSan Francisco, CA 941431811955438
  7. Evren Keles, M.D.San Francisco, CA 941431407872674
  8. Praveen Mummaneni, M.D.San Francisco, CA 941431407960099

Common questions

What is Margaret Riordan, MD's NPI number?

Margaret Riordan, MD's National Provider Identifier (NPI) is 1902061955, issued on Jul 18, 2008. An NPI identifies a provider in billing; it is not a license.

Where is Margaret Riordan, MD located?

The NPPES record lists a practice address at 400 Parnassus Ave, San Francisco, CA, 94143. Phone: (415) 472-1000. Providers update this record themselves, so call before visiting.

How can I verify Margaret Riordan, MD's license?

NPPES lists California license number 137141, 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 Margaret Riordan, MD's MIPS final score?

The 2023 MIPS final score is 91 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.