NPPES file of Aug 9, 2026

Merl Arthur Charles, MD PHD

Endocrinology, Diabetes & Metabolism Physician · San Francisco, CA

Merl Arthur Charles, MD PHD is an endocrinology, diabetes & metabolism physician with a practice address in San Francisco, California, and NPI 1023152055, issued on Feb 15, 2007. Check the license (California G22463, 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 and 2024 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1023152055
Name
Merl Arthur Charles
Credential
MD PHD
Primary taxonomy
Endocrinology, Diabetes & Metabolism Physician 207RE0101X
License number
G22463 CA
Self-reported in NPPES; status is on the state search
Practice location
400 Parnassus Ave, San Francisco, CA 94143
Phone
(415) 476-1517
Enumerated
Feb 15, 2007
Record last updated
Jul 8, 2007 (not updated in 19 years: call before relying on the address or phone)
Medicare enrollment
Enrolled (PECOS I20070501000627); accepts Medicare assignment
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 Merl Arthur Charles in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license G22463
    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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97% fewer Medicare Part D claims than the average endocrinology, diabetes & metabolism physician in 2024

69 Medicare Part D claims, against an average of 2,630 among the 8,223 providers of this specialty who prescribed in Part D.

  1. Merl Charles69
  2. Specialty average2,630

Most prescribed

  1. Metformin Hcl15 claims
  2. Ezetimibe12 claims
  3. Lisinopril12 claims
  4. Glimepiride11 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.

The practice group's MIPS final score for 2023 (Medicare payment program): 74.5 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. Qualitynot scored (reweighted)
  2. Costout of 100 · 30%46.7
  3. Promoting interoperabilityout of 100 · 25%76.0
  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. University OF California San FranciscoSan Francisco, CA

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

Merl Arthur Charles among 1,131 endocrinology, diabetes & metabolism physician records in California

Merl Arthur Charles, MD PHD is one of 1,131 endocrinology, diabetes & metabolism physician records with a practice address in California. 84% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2007, is newer than 46% of them.

  • NPI issued2007 · 46% of these records are older, 42% newer
  • In a Medicare fileYes · 84% of these records are
  • In the CMS Doctors and Clinicians fileYes · 69% of these records are
  • Graduated1967 · median 2003 among the 779 with a school on file
  • Record last updated2007 · 57% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RE0101X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

Endocrinology, Diabetes & Metabolism Physician providers in California

There are 1,131 endocrinology, diabetes & metabolism physician records in California.

The 8 endocrinology, diabetes & metabolism physician records with the nearest ZIP codes

  1. Mark Anderson, MDSan Francisco, CA 941431013971001
  2. Lewis Blevins, MDSan Francisco, CA 941431295822393
  3. Ira Goldfine, MDSan Francisco, CA 941431508823675
  4. Eric Goldman, M.D.San Francisco, CA 941431922194869
  5. Elizabeth Holt, MDSan Francisco, CA 941431184607392
  6. Victoria Hsiao, MD, PHDSan Francisco, CA 941431659418655
  7. Martha Kennedy, M.D.San Francisco, CA 941431982651022
  8. Gregory Ku, MD PHDSan Francisco, CA 941431033241658

Common questions

What is Merl Arthur Charles, MD PHD's NPI number?

Merl Arthur Charles, MD PHD's National Provider Identifier (NPI) is 1023152055, issued on Feb 15, 2007. An NPI identifies a provider in billing; it is not a license.

Where is Merl Arthur Charles, MD PHD located?

The NPPES record lists a practice address at 400 Parnassus Ave, San Francisco, CA, 94143. Phone: (415) 476-1517. Providers update this record themselves, so call before visiting.

How can I verify Merl Arthur Charles, MD PHD's license?

NPPES lists California license number G22463, 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 Merl Arthur Charles, MD PHD prescribe under Medicare Part D?

In 2024, Merl Arthur Charles, MD PHD had 69 Medicare Part D claims; the average among endocrinology, diabetes & metabolism physician prescribers was 2,630. Part D covers Medicare prescriptions only.

What is Merl Arthur Charles, MD PHD's MIPS final score?

The 2023 MIPS final score is 74.5 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.