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PROVIDER PROFILE · NPI 1114964186

William O'callahanMD

PRACTICEURGENT CARE SPECIALISTS, P.C.See all providers at this practice →
Emergency MedicineHolden, MAI
CROSS-REFERENCE

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FACILITY AFFILIATIONS

Hospital & Facility Affiliations (1)

CCN 220163
Hospital
MEDICARE UTILIZATION · PART B · 2024
Total beneficiaries
958
Unique beneficiaries
—
Total services
988
Distinct HCPCS
14
Medicare payment
$68K
Peer benchmark
Q1
Q2
Q3
Q4
Q5
Total Medicare services vs. 1,329 Emergency Medicine providers in MA — top quintile (cohort median 399).
PRESCRIBING · PART D · 2024
Total Rx claims
715
Beneficiaries
—
Total drug cost
$7K
Distinct drugs
16
Brand share
23.1%
Top prescribed drugs
Doxycycline Hyclate144 claims
Ibuprofen128 claims
Azithromycin123 claims
Prednisone58 claims
Nitrofurantoin Monohyd/M-Cryst43 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.
REFERRAL NETWORK

Where William O'callahan'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). 26 inbound referrers · 111 outbound destinations.

Receives referrals from
Inbound — who sends patients here
PhysicianPatientsVisits
Hamid Salamipour
Diagnostic Radiology · Newton, MA
4378
Steven Miller
Diagnostic Radiology · Newton, MA
4265
THE GENERAL HOSPITAL CORPORATION4188
MASS GENERAL BRIGHAM HOME CARE, INC.3443
Iris Foley
Diagnostic Radiology · Newton, MA
2975
Quest Diagnostics Massachusetts Llc
Clinical Laboratory · Marlborough, MA
2846
Yamini Levitzky
Cardiology · Braintree, MA
2741
Edward Hurwitz
Hospitalist · Boston, MA
2543
SCHAFER, LEAH2338
FALLON SERVICE, INC.2231
CORRIGAN, BRENDA2248
POLGER, MARLA2135
Refers patients to
Outbound — where patients go next
PhysicianPatientsVisits
NEWTON-WELLESLEY HOSPITAL5741,654
Cataldo Ambulance Service Inc
Ambulance Service Provider · Somerville, MA
143399
CORRIGAN, BRENDA119173
FALLON SERVICE, INC.119196
Mark Weinfeld
Cardiology · Boston, MA
111185
Yamini Levitzky
Cardiology · Braintree, MA
109166
Giulia Sheftel
Cardiology · Newton, MA
102162
BOLANIS, NANCY101185
Matthew Hoimes
Diagnostic Radiology · Raleigh, NC
86152
HAMILTON, EDNA76129
Stefanos Parpos
Cardiology · Newton, MA
75113
Kee Chung
Diagnostic Radiology · Boston, MA
68118
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.