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PROVIDER PROFILE · NPI 1427052802

Warren JohnstonMD

CardiologyOrange, CAI
CROSS-REFERENCE

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MEDICARE UTILIZATION · PART B · 2024
Total beneficiaries
986
Unique beneficiaries
—
Total services
1,223
Distinct HCPCS
10
Medicare payment
$110K
Peer benchmark
Q1
Q2
Q3
Q4
Q5
Total Medicare services vs. 1,869 Cardiology providers in CA — below median (cohort median 2,371).
PRESCRIBING · PART D · 2024
Total Rx claims
5,260
Beneficiaries
—
Total drug cost
$997K
Distinct drugs
43
Brand share
20.2%
Top prescribed drugs
Rosuvastatin Calcium1,105 claims
Metoprolol Succinate551 claims
Amlodipine Besylate436 claims
Apixaban359 claims
Atorvastatin Calcium328 claims
QUALITY · MIPS · 2024
No data available for this provider in 2024.
INDUSTRY PAYMENTS · OPEN PAYMENTS · 2024
Total received
$542
Payment records
39
By payment type
Food and Beverage$542
REFERRAL NETWORK

Where Warren Johnston'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). 28 inbound referrers · 58 outbound destinations.

Receives referrals from
Inbound — who sends patients here
PhysicianPatientsVisits
Unilab Corporation
Clinical Laboratory · West Hills, CA
197568
Peter Piampiano
Diagnostic Radiology · Knoxville, TN
4991
Kirk Ohanian
Diagnostic Radiology · Fort Worth, TX
4863
Thomas Kim
Cardiology · Orange, CA
4675
Dan Vu
Diagnostic Radiology · Orange, CA
3753
Hieu Truong
Diagnostic Radiology · Orange, CA
3548
Mark Masotto
Diagnostic Radiology · Orange, CA
3260
Donald Mahon
Cardiology · Orange, CA
3246
Richard Cho
Interventional Radiology · Orange, CA
2434
Unilab Corporation
Clinical Laboratory · Orange, CA
2291
Kenneth Meng
Diagnostic Radiology · Orange, CA
2128
Michael Chan
Cardiology · Orange, CA
2041
Refers patients to
Outbound — where patients go next
PhysicianPatientsVisits
Unilab Corporation
Clinical Laboratory · West Hills, CA
173397
ST. JOSEPH HOSPITAL OF ORANGE168401
ST JOSEPH HOSPITAL OF ORANGE6792
Brian Kim
Clinical Cardiac Electrophysiology · Kearney, NE
51152
Falck Mobile Health Corp
Ambulance Service Provider · Orange, CA
4984
Thomas Kim
Cardiology · Orange, CA
4567
Michael Forino
Diagnostic Radiology · Orange, CA
4267
Joon Kim
Diagnostic Radiology · Orange, CA
3861
Andrew Knoll
Diagnostic Radiology · Orange, CA
3651
Mark Masotto
Diagnostic Radiology · Orange, CA
3455
Kirk Ohanian
Diagnostic Radiology · Fort Worth, TX
3357
Peter Piampiano
Diagnostic Radiology · Knoxville, TN
3248
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.