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PROVIDER PROFILE · NPI 1578705679

Margarita Castro-ZarragaM.D.

PRACTICED.A.W., L.L.C.See all providers at this practice →
Family PracticeLowell, MAI
CROSS-REFERENCE

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REFERRAL NETWORK

Where Margarita Castro-Zarraga'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). 48 inbound referrers · 0 outbound destinations.

Receives referrals from
Inbound — who sends patients here
PhysicianPatientsVisits
BETH ISRAEL DEACONESS HOSPITAL-NEEDHAM, INC.1632,088
NEWBRIDGE ON THE CHARLES, INC.142667
BRIARWOOD OPERATOR, LLC1101,005
FALLON SERVICE, INC.108609
Perminder Dhillon
Internal Medicine · Needham, MA
74426
Alexis Kelleher
Nurse Practitioner · Roslindale, MA
58470
FALLON EMERGENCY MEDICAL SERVICES, INC.49238
SULLIVAN, MARYELLEN43357
Quest Diagnostics Massachusetts Llc
Clinical Laboratory · Marlborough, MA
37109
Bruce Kaster
Geriatric Psychiatry · Needham, MA
31121
NI MHUIRCHEARTAIGH, JENNIFER29130
VIJAYAKUMAR, RADHA28306
Refers patients to
Outbound — where patients go next
No outbound pairs above the suppression threshold.
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.
MEDICARE UTILIZATION · PART B · 2024
Total beneficiaries
25
Unique beneficiaries
—
Total services
32
Distinct HCPCS
1
Medicare payment
$305
Peer benchmark
Q1
Q2
Q3
Q4
Q5
Total Medicare services vs. 1,348 Family Practice providers in MA — bottom quintile (cohort median 537).
PRESCRIBING · PART D · 2024
Total Rx claims
3,445
Beneficiaries
—
Total drug cost
$435K
Distinct drugs
68
Brand share
27.3%
Top prescribed drugs
Atorvastatin Calcium326 claims
Amlodipine Besylate203 claims
Albuterol Sulfate185 claims
Gabapentin179 claims
Lisinopril161 claims
QUALITY · MIPS · 2024
No data available for this provider in 2024.
INDUSTRY PAYMENTS · OPEN PAYMENTS · 2024
No data available for this provider in 2024.