2026 NPPES data Clinical Pathology/Laboratory Medicine Physician NPI 1649247602 MD
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BONNIE BALZER, MD

Clinical Pathology/Laboratory Medicine Physician in SAN FRANCISCO, 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.
Prescribing volume
17
Medicare Part D claims · Clinical Pathology/Laboratory Medicine Physician avg: 149
MIPS score
63.51/100
▼ 20 pts below national avg 83.1 · [object Object]
What the federal data reveals: BONNIE BALZER, MD is a Clinical Pathology/Laboratory Medicine Physician ([object Object]) practicing in SAN FRANCISCO, California with a Medicare Part D prescribing footprint of 17 claims . Their CMS MIPS Final Score of 63.51/100 (national average: 83.1) reflects performance across Quality, Cost, Interoperability, and Improvement Activities .

What stands out: BONNIE BALZER, MD reported a CMS MIPS final score of 63.51 out of 100, below the 83.1 national average, and filed 17 Medicare Part D claims in 2023. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

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

BONNIE BALZER, MD at a glance

Below national average

NPI registry status

Active

Issued 03/08/2006

NPI 1649247602

Primary specialty

Clinical Pathology/Laboratory Medicine Physician

Niche

1,229 US NPIs in this specialty

Medicare Part D claims

17 89% vs specialty avg

2023 prescription claims

Specialty avg: 149

MIPS final score

63.51/100 19.589999999999996% pts

Mid-tier band

vs 83.1 national avg

Specialty distribution in California

How Clinical Pathology/Laboratory Medicine Physician compares to other specialties among California providers

California providers

Clinical Pathology/Laboratory Medicine Physician share within California

1. Clinical Pathology/Laboratory Medicine Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Clinical Pathology/Laboratory Medicine Physician share within California

Medicare quality performance — MIPS

BONNIE BALZER, MD's 2023 MIPS final score plotted against the Clinical Pathology/Laboratory Medicine Physician national average

Below national average
MIPS Final Score
63.51/100
vs 83.1 national avg · 2023 performance year

MIPS final score (Clinical Pathology/Laboratory Medicine Physician) — 63.51/100 vs national avg 83.1

0%100%National avg83%63.5%
MIPS final score (Clinical Pathology/Laboratory Medicine Physician) — 63.51/100 vs national avg 83.1

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).

BONNIE BALZER, MD is a Clinical Pathology/Laboratory Medicine Physician provider practicing in SAN FRANCISCO, California, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: MD. NPI: 1649247602. 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.

BONNIE BALZER, MD appears in the CMS NPPES registry as a Clinical Pathology/Laboratory Medicine Physician provider holding MD credentials at 3700 CALIFORNIA ST, SAN FRANCISCO, CA, 94118, with a listed phone of (415) 750-6095. NPI 1649247602 was issued on 03/08/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what BALZER 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 records for calendar year 2023 show 17 prescription claims written by this provider, covering N/A Medicare beneficiaries and totaling roughly $340 in drug spend. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 63.51/100 for the 2023 performance year (Quality 53.3817), compared with the national average of 83.1.

Clinical Pathology/Laboratory Medicine Physician is a narrow specialty nationwide, with 1,229 enrolled providers across 51 states and an average of 149 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

3700 CALIFORNIA ST
SAN FRANCISCO, CA 94118

Provider Details

NPI 1649247602
Specialty Clinical Pathology/Laboratory Medicine Physician
Credentials MD
Gender Female
NPI Issued 03/08/2006

CMS Quality Score (MIPS)

Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.

63.51
Final Score
Avg: 83.1
53.3817
Quality

Reporting: Group practice

Hospital and facility affiliations

Facilities where BONNIE BALZER, MD 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.

CEDARS-SINAI MEDICAL CARE FOUNDATION
IRVINE, 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 BONNIE BALZER, MD. To verify BONNIE BALZER, MD'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.

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

17
Total Claims
$340
Total Drug Cost
N/A
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
17
Total Day Supply
259
Brand Drug Cost
$0
Generic Drug Cost
$340

Patient Demographics

Average Patient Age
91.0 years
Avg HCC Risk Score
1.13

Clinical Pathology/Laboratory Medicine Physician Overview

How BONNIE BALZER, MD fits within the Clinical Pathology/Laboratory Medicine Physician landscape nationally.

1,229
Clinical Pathology/Laboratory Medicine Physician Providers in US
51
States with Clinical Pathology/Laboratory Medicine Physician
149
Avg Claims per Provider

BONNIE BALZER, MD's 17 claims are below the specialty average of 149.

Nearby Clinical Pathology/Laboratory Medicine Physician Providers in California

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

Compare Clinical Pathology/Laboratory Medicine Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is BONNIE BALZER, MD's specialty?
BONNIE BALZER, MD specializes in Clinical Pathology/Laboratory Medicine Physician and practices in SAN FRANCISCO, California. Credentials: MD.
How much does BONNIE BALZER, MD prescribe under Medicare Part D?
In 2023, BONNIE BALZER, MD wrote 17 Medicare Part D claims totaling $340 in drug costs for N/A beneficiaries.
What is BONNIE BALZER, MD's Medicare quality score?
BONNIE BALZER, MD has a CMS MIPS Final Score of 63.51/100 (Quality: 53.3817). The national average MIPS Final Score is 83.1. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is BONNIE BALZER, MD located?
BONNIE BALZER, MD is located at 3700 CALIFORNIA ST, SAN FRANCISCO, CA, 94118. Phone: (415) 750-6095.
What is BONNIE BALZER, MD's NPI number?
BONNIE BALZER, MD's National Provider Identifier (NPI) is 1649247602, issued on 03/08/2006.
How many Clinical Pathology/Laboratory Medicine Physician providers are there in the US?
There are 1,229 Clinical Pathology/Laboratory Medicine Physician providers across 51 states in the US. The average Clinical Pathology/Laboratory Medicine Physician provider writes 149 Medicare Part D claims per year.
Does BONNIE BALZER, MD accept Medicare?
BONNIE BALZER, MD appears in CMS Medicare data with 17 Part D claims and N/A Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify BONNIE BALZER, MD's credentials?
BONNIE BALZER, MD's NPI is 1649247602 with credentials MD. 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.
Prescribing Data
CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
Quality Performance
CMS Merit-based Incentive Payment System (MIPS) — 2023 performance year.
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