caretrace.iopowered by▸healthparse
SearchCohort Builder
Tools▾
KOL FinderTerritoriesDrug Compare
AI Query
Browse▾
By stateBy specialty
Pricing
SearchCohort BuilderToolsKOL FinderTerritoriesDrug CompareAI QueryBrowseBy stateBy specialtyPricing
PROVIDER PROFILE · NPI 1497744247

Mark O'brienD.O.

Internal MedicineVista, CAI
CROSS-REFERENCE

Related data on other Healthparse brands

ProviderScore
OIG/SAM exclusion screening, sanctions history
© 2026 CareTrace
PricingContactPrivacyTerms
QUALITY · MIPS · 2024
No data available for this provider in 2024.
MEDICARE UTILIZATION · PART B · 2024
Total beneficiaries
374
Unique beneficiaries
—
Total services
657
Distinct HCPCS
4
Medicare payment
$57K
Peer benchmark
Q1
Q2
Q3
Q4
Q5
Total Medicare services vs. 10,499 Internal Medicine providers in CA — above median (cohort median 531).
INDUSTRY PAYMENTS · OPEN PAYMENTS · 2024
No data available for this provider in 2024.
PRESCRIBING · PART D · 2024
Total Rx claims
36
Beneficiaries
—
Total drug cost
$192
Distinct drugs
3
Brand share
0.0%
Top prescribed drugs
Levofloxacin13 claims
Doxycycline Hyclate12 claims
Furosemide11 claims
REFERRAL NETWORK

Where Mark O'brien'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). 15 inbound referrers · 36 outbound destinations.

Receives referrals from
Inbound — who sends patients here
PhysicianPatientsVisits
Victor Souza
Internal Medicine · Vista, CA
59115
Sean Pinnell
Diagnostic Radiology · Vista, CA
46110
Jennifer Mayberry
Diagnostic Radiology · Portland, OR
3364
Kiran Patel
Diagnostic Radiology · Oceanside, CA
2960
NPI 10634734292546
William Kakimoto
Diagnostic Radiology · La Jolla, CA
2349
City Of Vista California
Ambulance Service Provider · Vista, CA
2139
Oscar Matthews
Internal Medicine · Vista, CA
2047
Chad Bernhardt
Emergency Medicine · Oceanside, CA
2031
Tan Nguyen
Diagnostic Radiology · Dallas, TX
1732
Kenneth Carr
Cardiology · Oceanside, CA
1735
Sean Lindstedt
Internal Medicine · Reno, NV
1517
Refers patients to
Outbound — where patients go next
PhysicianPatientsVisits
TRI-CITY HOSPITAL194396
BALBOA AMBULANCE INC.69122
Stephen Schmitter
Diagnostic Radiology · Dallas, TX
54127
Bruce Biederman
Diagnostic Radiology · Oceanside, CA
51111
Steven Epner
Diagnostic Radiology · Oceanside, CA
47106
Victor Souza
Internal Medicine · Vista, CA
4570
TRI CITY HOSPITAL3657
City Of Oceanside
Ambulance Service Provider · Oceanside, CA
3362
Sean Pinnell
Diagnostic Radiology · Vista, CA
3079
Kan-Di-Ki Llc
Portable X-Ray Supplier · North Hollywood, CA
28127
Jennifer Mayberry
Diagnostic Radiology · Portland, OR
2756
David Spiegel
Internal Medicine · Vista, CA
2176
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.