May Yen Yau, MD

Medicare activity in 2024

Official CMS public-use data for May Yen Yau, 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.

Most frequent services

1. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)327 services
2. Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit (G0439)142 services
3. Annual depression screening, 5 to 15 minutes (G0444)140 services
4. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)105 services
5. Administration of influenza virus vaccine (G0008)67 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 cholesterol72%
• High blood pressure52%
• Arthritis29%
• Osteoporosis24%
• Cancer (breast, colorectal, lung, prostate, endometrial or leukemia/lymphoma)22%
• Chronic kidney disease18%

Hospitals where May Yen Yau works

Medicare's Facility Affiliation Data lists May Yen Yau 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.

• California Pacific Medical Center- Van Ness CampusSan Francisco, CA · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 050047
• California Pacific Medical Center-Davies Campus HospitalSan Francisco, CA · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: not listed by Medicare · CCN 050008

Practice locations

Addresses where May Yen Yau is enrolled with Medicare (CMS data updated October 2, 2026).

• 2100 Webster St, Suite 423San Francisco, CA 94115 (415) 923‑3878

Group practices

Medicare enrollment lists May Yen Yau as a member of this group (CMS data updated October 2, 2026).

• Pacific Internal Medicine Associates5 clinicians in the group

Specialties

• Internal Medicineprimary

Find other Internal Medicine doctors in California →

Other internal medicine doctors in San Francisco

Clinicians with the same Medicare primary specialty in San Francisco, CA — not a recommendation.

• Lily Chu, MD
• Elizabeth Dzeng, MD
• Rebecca Hayes, MD
• Dorothy Hui-Jia Tan, MD
• Naissem L. Andemel, MD
• Janet Y. Lee
• Charles U. Delatore, MD
• Gabriel M. Ortiz, MD

All internal medicine doctors in San Francisco →

Other clinicians in Pacific Internal Medicine Associates

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

• Arlene P. Keller, MD
• Annette Y. Kwon, MD
• Yukako Honda, MD
• Susan J. Ripper, MD

Clinician information

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

1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
6. Medicare Care Compare — official Medicare tool to look up clinicians