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Compare the published Medicare service mix of Elizabeth E Obrien, M.D. with clinicians in the same registry specialty: Internal Medicine.

IL · Exact areaEdit location

2024 published service data · 500 eligible profiles compared. This search reached its 500-profile comparison limit, using NPI order. Narrow the location for a more focused comparison. Similarity describes billing patterns, not quality, outcomes, or suitability for your care.

Raul V Guerrero, MD

Internal Medicine · Ottawa, IL

Shared published services
2 shared services · view billing descriptions
  • Blood test, clotting time (85610)
  • Insertion of needle into vein for collection of blood sample (36415)
57%Service-mix similarityView profile →

Sambasivam Suthan, M.D

Internal Medicine · Highland, IL

Shared published services
1 shared services · view billing descriptions
  • Insertion of needle into vein for collection of blood sample (36415)
53%Service-mix similarityView profile →

Hajira Younas Khan, MD

Internal Medicine · Downers Grove, IL

Shared published services
3 shared services · view billing descriptions
  • Blood test, clotting time (85610)
  • Insertion of needle into vein for collection of blood sample (36415)
  • Automated urinalysis test (81003)
44%Service-mix similarityView profile →

Terence P Sullivan, MD

Internal Medicine · Chicago, IL

Shared published services
2 shared services · view billing descriptions
  • Insertion of needle into vein for collection of blood sample (36415)
  • Automated urinalysis test (81003)
40%Service-mix similarityView profile →

Angelo Andrew Costas, M.D.

Internal Medicine · Chicago, IL

Shared published services
2 shared services · view billing descriptions
  • Insertion of needle into vein for collection of blood sample (36415)
  • Automated urinalysis test (81003)
40%Service-mix similarityView profile →

Roger S. Mcclintock, M.D.

Internal Medicine · Taylorville, IL

Shared published services
2 shared services · view billing descriptions
  • Insertion of needle into vein for collection of blood sample (36415)
  • Amplifed dna or rna probe detection of severe acute respiratory syndrome coronavirus 2 (covid-19) antigen (87635)
39%Service-mix similarityView profile →

Dominic K Leung, MD

Internal Medicine · Chicago, IL

Shared published services
2 shared services · view billing descriptions
  • Blood test, clotting time (85610)
  • Insertion of needle into vein for collection of blood sample (36415)
39%Service-mix similarityView profile →

David Pittman, M.D.

Internal Medicine · Springfield, IL

Shared published services
2 shared services · view billing descriptions
  • Blood test, clotting time (85610)
  • Insertion of needle into vein for collection of blood sample (36415)
36%Service-mix similarityView profile →

David Zich, MD

Internal Medicine · Chicago, IL

Shared published services
2 shared services · view billing descriptions
  • Insertion of needle into vein for collection of blood sample (36415)
  • Automated urinalysis test (81003)
36%Service-mix similarityView profile →

Michael S Morrow, MD

Internal Medicine · Spring Valley, IL

Shared published services
2 shared services · view billing descriptions
  • Blood test, clotting time (85610)
  • Insertion of needle into vein for collection of blood sample (36415)
35%Service-mix similarityView profile →

Deepak Mitra, MD

Internal Medicine · Mchenry, IL

Shared published services
2 shared services · view billing descriptions
  • Insertion of needle into vein for collection of blood sample (36415)
  • Automated urinalysis test (81003)
34%Service-mix similarityView profile →

Nader Sallam, MD

Internal Medicine · Ingleside, IL

Shared published services
2 shared services · view billing descriptions
  • Insertion of needle into vein for collection of blood sample (36415)
  • Automated urinalysis test (81003)
32%Service-mix similarityView profile →
How this comparison works

We use the same calendar year of CMS Medicare Physician & Other Practitioners data for both providers. Published non-drug service counts are combined by HCPCS code across places of service. We apply log(1 + count), normalize the vectors, and compare them using cosine similarity.

Candidates share the reference provider’s current NPPES primary taxonomy and match the location you enter. We examine up to 500 candidates in NPI order, then show up to 12 with the highest positive similarity within that set. The score is not a percentile, medical recommendation, or prediction. Suppressed services are not estimated. Medicare fee-for-service data does not describe a provider’s entire practice.

Source: CMS Medicare Physician & Other Practitioners - by Provider and Service : 2024-12-01 · Published May 21, 2026.