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PROVIDER PROFILE · NPI 1245246164

John MarshburnM.D.

OphthalmologyPlacentia, CAI
CROSS-REFERENCE

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ProviderScore
OIG/SAM exclusion screening, sanctions history
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QUALITY · MIPS · 2024
Final MIPS score
75.0
Quality
0.0
Cost
0.0
Improvement activities
0.0
Promoting interop.
0.0
Payment adjustment
0.00%
Group
PRESCRIBING · PART D · 2024
Total Rx claims
2,608
Beneficiaries
—
Total drug cost
$346K
Distinct drugs
27
Brand share
35.9%
Top prescribed drugs
Latanoprost951 claims
Bimatoprost261 claims
Timolol Maleate194 claims
Dorzolamide Hcl/Timolol Maleat186 claims
Dorzolamide Hcl140 claims
MEDICARE UTILIZATION · PART B · 2024
Total beneficiaries
3,699
Unique beneficiaries
—
Total services
6,474
Distinct HCPCS
14
Medicare payment
$308K
Peer benchmark
Q1
Q2
Q3
Q4
Q5
Total Medicare services vs. 2,144 Ophthalmology providers in CA — top quintile (cohort median 1,859).
INDUSTRY PAYMENTS · OPEN PAYMENTS · 2024
No data available for this provider in 2024.
REFERRAL NETWORK

Where John Marshburn's patients come from & go

Directional shared-patient flow from Medicare claims — who sends patients to this provider (inbound) and where this provider's patients go next (outbound). 29 inbound referrers · 57 outbound destinations.

Receives referrals from
Inbound — who sends patients here
PhysicianPatientsVisits
ST JUDE HOSPITAL INC171294
Unilab Corporation
Clinical Laboratory · West Hills, CA
163389
Victor Lee
Pathology · Oceanside, CA
122286
Paul Weinstein
Cardiology · Fullerton, CA
3068
Shahla Sadighian
Internal Medicine · Placentia, CA
24108
Timothy You
Ophthalmology · Santa Ana, CA
2458
HARRIS HISTOLOGY SERVICES2328
Alexander Miller
Dermatology · Yorba Linda, CA
2345
Kenneth Birkenstein
Family Practice · Yorba Linda, CA
2055
PIH HEALTH WHITTIER HOSPITAL1854
Ramesh Rathod
Interventional Cardiology · Fullerton, CA
1729
UNGER, PHILLIP1621
Refers patients to
Outbound — where patients go next
PhysicianPatientsVisits
Unilab Corporation
Clinical Laboratory · West Hills, CA
175396
ST JUDE HOSPITAL INC137225
Victor Lee
Pathology · Oceanside, CA
135247
UNIVERSITY OF CALIFORNIA IRVINE131437
Laboratory Corporation Of America
Clinical Laboratory · San Diego, CA
67119
UNIVERSITY OF CALIFORNIA IRVINE3181
Paul Weinstein
Cardiology · Fullerton, CA
3068
Alexander Miller
Dermatology · Yorba Linda, CA
3060
Timothy You
Ophthalmology · Santa Ana, CA
2961
Shahla Sadighian
Internal Medicine · Placentia, CA
26149
Quest Diagnostics Nichols Institute
Clinical Laboratory · San Juan Capistrano, CA
2656
Kenneth Birkenstein
Family Practice · Yorba Linda, CA
2465
Source: CMS Physician Shared Patient Patterns (30-day window, Medicare FFS). Direction = a beneficiary seen by the first provider, then the second, within 30 days; a proxy for referral, not a documented referral. Pairs with fewer than 11 shared beneficiaries are suppressed.