2026 NPPES data Hematology (Pathology) Physician NPI 1477990125 DO
Verify on CMS →

JOHN GRAFF, DO

Hematology (Pathology) Physician in SACRAMENTO, California. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
What the federal data reveals: JOHN GRAFF, DO is a Hematology (Pathology) Physician ([object Object]) practicing in SACRAMENTO, California .

What stands out: JOHN GRAFF, DO specializes in Hematology (Pathology) Physician and practices in SACRAMENTO, California, listed in the federal CMS National Provider Identifier registry. Every detail on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

JOHN GRAFF, DO practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation — signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).

JOHN GRAFF, DO at a glance

Quality data not reported

NPI registry status

Active

Issued 06/03/2013

NPI 1477990125

Primary specialty

Hematology (Pathology) Physician

Niche

745 US NPIs in this specialty

Specialty distribution in California

How Hematology (Pathology) Physician compares to other specialties among California providers

California providers

Hematology (Pathology) Physician share within California

1. Hematology (Pathology) Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Hematology (Pathology) Physician share within California

Specialty board-certification context

Estimated specialty board-certified rate — Hematology (Pathology) Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Hematology (Pathology) Physician ABMS/AOA estimate

Est. board-certified rate (Hematology (Pathology) Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Hematology (Pathology) Physician) — ABMS / AOA estimate

The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.

Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).

JOHN GRAFF, DO is a Hematology (Pathology) Physician provider practicing in SACRAMENTO, California, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: DO. NPI: 1477990125. This profile includes practice location, specialty classification, and organizational affiliations from the CMS provider registry. Provider information is self-reported to CMS and updated monthly.

JOHN GRAFF, DO appears in the CMS NPPES registry as a Hematology (Pathology) Physician provider holding DO credentials at 4400 V ST STE 1107, SACRAMENTO, CA, 95817, with a listed phone of (916) 734-0299. NPI 1477990125 was issued on 06/03/2013. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what GRAFF most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D prescribing data is not currently published for this NPI, which typically means the provider either wrote fewer than 11 Part D claims in the most recent reporting year, does not participate in Medicare, or practices in a specialty that rarely prescribes outpatient drugs. Absence of prescribing data is not a quality signal — many Hematology (Pathology) Physician providers operate outside Part D entirely.

Hematology (Pathology) Physician is a narrow specialty nationwide, with 745 enrolled providers across 46 states and an average of 617 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.

Practice Address

4400 V ST STE 1107
SACRAMENTO, CA 95817

Provider Details

NPI 1477990125
Specialty Hematology (Pathology) Physician
Credentials DO
Gender Male
NPI Issued 06/03/2013

Hospital and facility affiliations

Facilities where JOHN GRAFF, DO bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" — a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.

REGENTS OF THE UNIV OF CA
SACRAMENTO, CA

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

License & disciplinary context — California MBC 2023 annual report

Aggregate state board data only — NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~150K California medical licensees in 2023 — they are NOT specific to JOHN GRAFF, DO. To verify JOHN GRAFF, DO's current license status, search the MBC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

576
Total board actions, California 2023
Across 556 cases
3.84
Actions per 1,000 licensees
California statewide rate
probation
Most common action type
186 cases

MBC publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the California disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Hematology (Pathology) Physician Overview

How JOHN GRAFF, DO fits within the Hematology (Pathology) Physician landscape nationally.

745
Hematology (Pathology) Physician Providers in US
46
States with Hematology (Pathology) Physician
617
Avg Claims per Provider

Nearby Hematology (Pathology) Physician Providers in California

Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as GRAFF.

Compare Hematology (Pathology) Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is JOHN GRAFF, DO's specialty?
JOHN GRAFF, DO specializes in Hematology (Pathology) Physician and practices in SACRAMENTO, California. Credentials: DO.
Where is JOHN GRAFF, DO located?
JOHN GRAFF, DO is located at 4400 V ST STE 1107, SACRAMENTO, CA, 95817. Phone: (916) 734-0299.
What is JOHN GRAFF, DO's NPI number?
JOHN GRAFF, DO's National Provider Identifier (NPI) is 1477990125, issued on 06/03/2013.
How many Hematology (Pathology) Physician providers are there in the US?
There are 745 Hematology (Pathology) Physician providers across 46 states in the US. The average Hematology (Pathology) Physician provider writes 617 Medicare Part D claims per year.
Does JOHN GRAFF, DO accept Medicare?
JOHN GRAFF, DO appears in CMS Medicare data. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify JOHN GRAFF, DO's credentials?
JOHN GRAFF, DO's NPI is 1477990125 with credentials DO. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.

Data Sources

Provider Directory
CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
Specialty Classification
NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
Limitations
Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.

See our complete data methodology for details on how we collect and process government data.

Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).

Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology