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Compare the published Medicare service mix of Christopher Lozano Orpiano, D.O. with clinicians in the same registry specialty: Gastroenterology · Internal Medicine (CMS).

CA · 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.

Manan A Jhaveri, MD

Internal Medicine (CMS) · Sacramento, CA

Shared published services
3 shared services · view billing descriptions
  • Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)
  • Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)
  • Biopsy of large bowel using a flexible endoscope (45380)
78%Service-mix similarityView profile →

Prathibha Chandrasekaran, M.D.

Gastroenterology (CMS) · Redding, CA

Shared published services
3 shared services · view billing descriptions
  • Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)
  • Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)
  • Biopsy of large bowel using a flexible endoscope (45380)
75%Service-mix similarityView profile →

Carlton Wayne Thomas, M.D.

Gastroenterology (CMS) · San Diego, CA

Shared published services
3 shared services · view billing descriptions
  • Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)
  • Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)
  • Biopsy of large bowel using a flexible endoscope (45380)
73%Service-mix similarityView profile →

Liana Vesga, MD

Gastroenterology · Internal Medicine (CMS) · Oakland, CA

Shared published services
3 shared services · view billing descriptions
  • Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)
  • Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)
  • Biopsy of large bowel using a flexible endoscope (45380)
73%Service-mix similarityView profile →

Alexander T. Lee, MD

Gastroenterology · Internal Medicine (CMS) · Woodland Hills, CA

Shared published services
3 shared services · view billing descriptions
  • Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)
  • Biopsy of large bowel using a flexible endoscope (45380)
  • Diagnostic exam of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43235)
73%Service-mix similarityView profile →

Christopher Daniel James Romberg, MD

Gastroenterology · Internal Medicine (CMS) · Cameron Park, CA

Shared published services
3 shared services · view billing descriptions
  • Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)
  • Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)
  • Diagnostic exam of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43235)
72%Service-mix similarityView profile →

Maher Tama, M.D.

Gastroenterology (CMS) · Walnut Creek, CA

Shared published services
3 shared services · view billing descriptions
  • Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)
  • Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)
  • Biopsy of large bowel using a flexible endoscope (45380)
72%Service-mix similarityView profile →

Ali Mohammed Syed, M.D.

Gastroenterology · Internal Medicine (CMS) · Ridgecrest, CA

Shared published services
3 shared services · view billing descriptions
  • Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)
  • Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)
  • Diagnostic exam of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43235)
72%Service-mix similarityView profile →

Tegpal Atwal

Gastroenterology (CMS) · Saint Helena, CA

Shared published services
3 shared services · view billing descriptions
  • Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)
  • Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)
  • Biopsy of large bowel using a flexible endoscope (45380)
71%Service-mix similarityView profile →

Usman G Rahim, M.D.

Gastroenterology (CMS) · Orange, CA

Shared published services
3 shared services · view billing descriptions
  • Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)
  • Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)
  • Biopsy of large bowel using a flexible endoscope (45380)
70%Service-mix similarityView profile →

W. David Mello, M.D.

Gastroenterology (CMS) · Glendale, CA

Shared published services
3 shared services · view billing descriptions
  • Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)
  • Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)
  • Biopsy of large bowel using a flexible endoscope (45380)
69%Service-mix similarityView profile →

Katherine Kim, MD

Gastroenterology · Internal Medicine (CMS) · Whittier, CA

Shared published services
3 shared services · view billing descriptions
  • Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)
  • Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)
  • Biopsy of large bowel using a flexible endoscope (45380)
69%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.