Quick answers
- Does Yi Zheng accept Medicare assignment?
- Yes. Medicare's clinician data says Yi Zheng accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Yi Zheng see?
- In 2024, CMS data shows 565 Original Medicare patients and 1,735 services for Yi Zheng. This counts Original Medicare only and measures volume, not quality.
- What is Yi Zheng's NPI number?
- 1851622427. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Yi Zheng, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 565 |
|---|---|
| Services billed to Medicare | 1,735 |
| Different services or procedures | 29 |
| Participating Medicare provider | Yes |
| Average age of these patients | 73 |
Most frequent services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)623 services
- New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more (99204)198 services
- Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)160 services
- Biopsy of large bowel using a flexible endoscope (45380)160 services
- Biopsy of small bowel (except ileum) using an endoscope (44361)150 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High cholesterol75%
- High blood pressure65%
- Arthritis38%
- Diabetes25%
- Anxiety20%
- Ischemic heart disease17%
Hospitals where Yi Zheng works
Medicare's Facility Affiliation Data lists Yi Zheng at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- John Muir Medical Center - Concord CampusConcord, CA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 050496
- John Muir Medical Center - Walnut Creek CampusWalnut Creek, CA · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 050180
Practice locations
Addresses where Yi Zheng is enrolled with Medicare (CMS data updated October 2, 2026).
- 2121 Ygnacio Valley Rd, Suite E105Walnut Creek, CA 94598 (925) 384‑9276
Specialties
- Gastroenterologyprimary
- Internal Medicinealso
Other gastroenterologists in Walnut Creek
Clinicians with the same Medicare primary specialty in Walnut Creek, CA — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1998 (28 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1851622427 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians