Loading...
NPI 1639146442 · San Gabriel, CA · Gastroenterology Physician
Customize your policy alerts
Get alerted when relevant policies change without checking for updates manually.
Monitor payer policy activity
Chester Zahn is a gastroenterology physician provider located in San Gabriel, California. This profile covers 19 Medicare and 13 Medicaid CPT/HCPCS procedure codes, with claims volume, average reimbursement, and total revenue by code, benchmarked against other providers billing the same services.
Provider details (source: NPPES NPI Registry)
| Field | Value |
|---|---|
| Entity Type | Individual |
| Organization | Chester Zahn |
| Address | 1026 E Las Tunas Dr |
| City | San Gabriel |
| State | CA |
| ZIP | 91776 |
| Taxonomy | Gastroenterology Physician |
| NPI Enumerated | March 1, 2006 |
Lifetime revenue by payer source (source: CMS Medicare & Medicaid claims data)
| Payer Source | Total Paid |
|---|---|
| Medicare | $239K |
| Medicaid | $175.6K |
Medicare revenue breakdown by CPT/HCPCS procedure code.
View: Bar Chart1 / 2
The CPT/HCPCS codes generating the most Medicare revenue for this provider.
19 rows
| CPT/HCPCS Code | Description | Claims | Avg Paid | Revenue |
|---|---|---|---|---|
| 99213 | The provider sees an established patient for an office visit or other outpatient visit involving evaluation and management. The visit involves a low level of medical decision making, and/or the… | 980 | $70 | $69.6K |
| 99222 | The provider sees a patient for an initial hospital inpatient or observation care visit involving evaluation and management (E/M). The visit involves a moderate level of medical decision making or… | 290 | $110 | $31.4K |
| 99232 | The provider sees a patient for a subsequent hospital inpatient or observation care visit involving evaluation and management (E/M). The visit involves a moderate level of medical decision making or… | 430 | $70 | $29.2K |
| 99204 | The provider sees a new patient for an office visit or other outpatient visit involving evaluation and management. The visit involves a moderate level of medical decision making, and/or the provider… | 200 | $140 | $27.3K |
| 45388 | In this procedure, the provider performs flexible colonoscopy to destroy one or more tumors, polyps, or other lesions. The procedure includes, but does not require, guide wire passage and dilating… | 60 | $230 | $13.3K |
| G0105 | Colorectal cancer screening; colonoscopy on individual at high risk | 60 | $180 | $11.3K |
| 43239 | The provider inserts a flexible endoscope through the mouth and down into the esophagus, stomach, and duodenum where he removes one or more tissue biopsy specimens for diagnostic analysis. | 150 | $70 | $10.1K |
| 99231 | The provider sees a patient for a subsequent hospital inpatient or observation care visit involving evaluation and management (E/M). The visit involves a straightforward or low level of medical… | 220 | $40 | $9.4K |
| 43246 | The provider inserts a flexible endoscope through the mouth and down into the esophagus, stomach, and duodenum to direct the placement of a tube through the skin and abdominal tissues into the… | 50 | $160 | $8.4K |
| 43255 | An esophagogastroduodenoscopy is a procedure to view the esophagus, stomach, and duodenum by means of flexible endoscope through the mouth. During the procedure, the provider stops patient bleeding. | 30 | $160 | $5.1K |
Showing 1–10 of 19
How this provider's Medicare billing volume and revenue compare to other providers nationally and within its state, across 19 CPT/HCPCS codes.
View: State1 / 2
Full comparison — all codes billed, vs. state median
19 rows
| CPT/HCPCS Code | Rank | Provider Count | Median Claims | Avg Paid | Average Revenue |
|---|---|---|---|---|---|
| 99233 | 8,710 | 11,530 | 120 | $100 | $26.2K |
| 45380 | 1,331 | 1,460 | 60 | $230 | $23.8K |
| 43239 | 328 | 1,500 | 80 | $150 | $17.3K |
| 99232 | 1,614 | 12,280 | 90 | $70 | $16.3K |
| G0105 | 110 | 650 | 30 | $340 | $14.8K |
| 45388 | 8 | 40 | 20 | $360 | $13.2K |
| 99213 | 1,090 | 34,660 | 80 | $70 | $13.2K |
| 99223 | 9,911 | 13,190 | 50 | $140 | $11.3K |
| 43251 | 37 | 130 | 20 | $350 | $9.4K |
| 99204 | 709 | 19,360 | 40 | $120 | $7.2K |
Showing 1–10 of 19
Medicaid revenue breakdown by year and by CPT/HCPCS procedure code, including monthly billing trends and the top codes driving revenue.
View: By Year1 / 3
Every CPT/HCPCS code this provider has billed to Medicaid, with claims volume, average payment, and total revenue.
13 rows
| CPT/HCPCS Code | Description | Claims | Avg Paid | Revenue |
|---|---|---|---|---|
| 99204 | The provider sees a new patient for an office visit or other outpatient visit involving evaluation and management. The visit involves a moderate level of medical decision making, and/or the provider… | 820 | $60 | $48.6K |
| 99203 | The provider sees a new patient for an office visit or other outpatient visit involving evaluation and management. The visit involves a low level of medical decision making, and/or the provider… | 910 | $40 | $31.9K |
| 99213 | The provider sees an established patient for an office visit or other outpatient visit involving evaluation and management. The visit involves a low level of medical decision making, and/or the… | 1,450 | $20 | $21.8K |
| 99215 | The provider sees an established patient for an office visit or other outpatient visit involving evaluation and management. The visit involves a high level of medical decision making, and/or the… | 230 | $70 | $15.8K |
| 99222 | The provider sees a patient for an initial hospital inpatient or observation care visit involving evaluation and management (E/M). The visit involves a moderate level of medical decision making or… | 320 | $50 | $14.9K |
| 43239 | The provider inserts a flexible endoscope through the mouth and down into the esophagus, stomach, and duodenum where he removes one or more tissue biopsy specimens for diagnostic analysis. | 170 | $80 | $13.4K |
| 99214 | The provider sees an established patient for an office visit or other outpatient visit involving evaluation and management. The visit involves a moderate level of medical decision making, and/or the… | 500 | $20 | $10.5K |
| 45378 | The provider examines the colon and rectum using a colonoscope, a flexible tube with a camera at its inserted end. If he sees any areas of abnormal mucosa or tissue, he takes samples using a brush… | 90 | $100 | $9.2K |
| 99231 | The provider sees a patient for a subsequent hospital inpatient or observation care visit involving evaluation and management (E/M). The visit involves a straightforward or low level of medical… | 220 | $20 | $4.3K |
| 45385 | The provider examines the colon and rectum using a colonoscope, a long, thin flexible tubular instrument with a light source and camera. He removes one or more tumors, polyps, or other lesions with a… | 10 | $170 | $2.1K |
Showing 1–10 of 13
How this provider's Medicaid billing volume and revenue compare to other California providers billing the same CPT/HCPCS codes.
Full comparison — all codes billed, vs. California median
13 rows
| CPT/HCPCS Code | Description | Rank | Provider Count | Median Claims | Avg Paid | Average Revenue |
|---|---|---|---|---|---|---|
| 43239 | The provider inserts a flexible endoscope through the mouth and down into the esophagus, stomach, and duodenum where he removes one or more tissue biopsy specimens for diagnostic analysis. | 487 | 780 | 350 | $180 | $200.7K |
| 99233 | The provider sees a patient for a subsequent hospital inpatient or observation care visit involving evaluation and management (E/M). The visit involves a high level of medical decision making or the… | 2,457 | 2,670 | 540 | $40 | $183.4K |
| 45385 | The provider examines the colon and rectum using a colonoscope, a long, thin flexible tubular instrument with a light source and camera. He removes one or more tumors, polyps, or other lesions with a… | 387 | 410 | 180 | $310 | $178.8K |
| 99214 | The provider sees an established patient for an office visit or other outpatient visit involving evaluation and management. The visit involves a moderate level of medical decision making, and/or the… | 7,192 | 13,300 | 640 | $40 | $169.6K |
| 45378 | The provider examines the colon and rectum using a colonoscope, a flexible tube with a camera at its inserted end. If he sees any areas of abnormal mucosa or tissue, he takes samples using a brush… | 311 | 530 | 140 | $240 | $158.4K |
| 99232 | The provider sees a patient for a subsequent hospital inpatient or observation care visit involving evaluation and management (E/M). The visit involves a moderate level of medical decision making or… | 2,426 | 2,840 | 490 | $40 | $139.6K |
| 99215 | The provider sees an established patient for an office visit or other outpatient visit involving evaluation and management. The visit involves a high level of medical decision making, and/or the… | 2,044 | 4,230 | 210 | $110 | $135K |
| 99213 | The provider sees an established patient for an office visit or other outpatient visit involving evaluation and management. The visit involves a low level of medical decision making, and/or the… | 5,723 | 14,520 | 760 | $10 | $122.8K |
| 99223 | The provider sees a patient for an initial hospital inpatient or observation care visit involving evaluation and management (E/M). The visit involves a high level of medical decision making or the… | 2,402 | 2,730 | 190 | $90 | $100.3K |
| 99204 | The provider sees a new patient for an office visit or other outpatient visit involving evaluation and management. The visit involves a moderate level of medical decision making, and/or the provider… | 1,401 | 5,870 | 180 | $70 | $73K |
Showing 1–10 of 13
Other providers in the same ZIP code as Chester Zahn, ranked by combined Medicare and Medicaid revenue.
| Provider | State | Taxonomy | Medicare Revenue | Medicaid Revenue |
|---|---|---|---|---|
| Aaron Jeng | CA | Internal Medicine Physician | $43.2M | $0 |
| David Chen | CA | Diagnostic Radiology Physician | $1.4M | $8.3K |
| Sid Danesh | CA | Dermatology Physician | $293.6K | $1.1M |
| Tai Wu | CA | Internal Medicine Physician | $1.3M | $10.9K |
| Second Bio Lab Clinical Laboratory | CA | Clinical Medical Laboratory | $536.6K | $160.5K |
| Joseph Lu | CA | Neurology Physician | $402.2K | $235.4K |
| Yih Kok | CA | Cardiovascular Disease Physician | $538K | $1.7K |
| Zhi Zeng | CA | Internal Medicine Physician | $367.4K | $140 |
| Chonghao Zhao | CA | Specialist | $280.3K | $0 |
| Jeffrey Young | CA | Family Medicine Physician | $155.1K | $0 |
Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.