Quick answers
- Does Anita C. Choy accept Medicare assignment?
- Yes. Medicare's clinician data says Anita C. Choy 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 Anita C. Choy see?
- In 2024, CMS data shows 166 Original Medicare patients and 5,140 services for Anita C. Choy. This counts Original Medicare only and measures volume, not quality.
- What is Anita C. Choy's NPI number?
- 1639136690. 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 Anita C. Choy, 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 | 166 |
|---|---|
| Services billed to Medicare | 5,140 |
| Different services or procedures | 20 |
| Participating Medicare provider | Yes |
| Average age of these patients | 74 |
Most frequent services
- Professional service for preparation and provision of 1 or more antigens (95165)2,112 services
- Test for allergy using allergenic extract (95004)994 services
- Professional service for multiple injections of allergen (95117)934 services
- Test for allergy using allergenic extract injected into skin (95024)400 services
- Test to measure the level of nitric oxide gas (95012)146 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 cholesterol71%
- High blood pressure52%
- Asthma47%
- Arthritis46%
- Osteoporosis24%
- Ischemic heart disease20%
Hospitals where Anita C. Choy works
Medicare's Facility Affiliation Data lists Anita C. Choy 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.
- Stanford Health CareStanford, CA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 050441
Practice locations
Addresses where Anita C. Choy is enrolled with Medicare (CMS data updated October 2, 2026).
- 211 Quarry Rd, Suite 106Palo Alto, CA 94304 (650) 322‑3847
Specialties
- Allergy/Immunologyprimary
Other allergist and immunologists in Palo Alto
Clinicians with the same Medicare primary specialty in Palo Alto, CA — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1986 (40 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) | 1639136690 |
| 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