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PROVIDER PROFILE · NPI 1003898131

Mark JohnstonMD

PRACTICELANCASTER GASTROENTEROLOGY, INC.See all providers at this practice →
GastroenterologyLancaster, PAI
CROSS-REFERENCE

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OIG/SAM exclusion screening, sanctions history
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QUALITY · MIPS · 2024
No data available for this provider in 2024.
FACILITY AFFILIATIONS

Hospital & Facility Affiliations (1)

CCN 390100
Hospital
PRESCRIBING · PART D · 2024
Total Rx claims
370
Beneficiaries
—
Total drug cost
$13K
Distinct drugs
5
Brand share
0.0%
Top prescribed drugs
Omeprazole219 claims
Pantoprazole Sodium68 claims
Famotidine50 claims
Esomeprazole Magnesium20 claims
Mesalamine13 claims
INDUSTRY PAYMENTS · OPEN PAYMENTS · 2024
Total received
$690
Payment records
32
By payment type
Food and Beverage$690
MEDICARE UTILIZATION · PART B · 2024
Total beneficiaries
472
Unique beneficiaries
—
Total services
1,627
Distinct HCPCS
13
Medicare payment
$79K
Peer benchmark
Q1
Q2
Q3
Q4
Q5
Total Medicare services vs. 771 Gastroenterology providers in PA — top quintile (cohort median 585).
REFERRAL NETWORK

Where Mark 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). 20 inbound referrers · 57 outbound destinations.

Receives referrals from
Inbound — who sends patients here
PhysicianPatientsVisits
LANCASTER GENERAL HOSPITAL173706
ROSE CITY HMA LLC3179
Lancaster Emergency Medical Services Association
Ambulance Service Provider · Millersville, PA
2845
Melissa Mckernan Pulliam
Clinical Cardiac Electrophysiology · Lancaster, PA
2243
Robert Martin
Nurse Practitioner · Lancaster, PA
2253
Patrick Weybright
Diagnostic Radiology · Lancaster, PA
2140
John Briguglio
Diagnostic Radiology · Hershey, PA
2136
Quest Diagnostics Clinical Laboratories Inc
Clinical Laboratory · Norristown, PA
19254
Paul Allegretti
Gastroenterology · Lancaster, PA
1856
Jeffrey Kramer
Diagnostic Radiology · Allentown, PA
1731
John Horwhat
Gastroenterology · Lancaster, PA
1327
Tareck Nossuli
Advanced Heart Failure and Transplant Cardiology · Lancaster, PA
1333
Refers patients to
Outbound — where patients go next
PhysicianPatientsVisits
LANCASTER GENERAL HOSPITAL191829
LANCASTER PA ENDOSCOPY ASC LLC105129
Fabien Baksh
Pathology · Lancaster, PA
8699
Dennis Horn
Certified Registered Nurse Anesthetist (CRNA) · York, PA
4965
ROSE CITY HMA LLC48161
Heather Saunders
Certified Registered Nurse Anesthetist (CRNA) · Lancaster, PA
3641
John Modene
Nurse Practitioner · Lancaster, PA
3463
Robert Martin
Nurse Practitioner · Lancaster, PA
2574
Christopher Farrell
Gastroenterology · Lancaster, PA
2562
Melissa Mckernan Pulliam
Clinical Cardiac Electrophysiology · Lancaster, PA
2450
Peter Eaton
Certified Registered Nurse Anesthetist (CRNA) · Lancaster, PA
2424
Thomas Brooks
Diagnostic Radiology · Lancaster, PA
2028
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.