Alexander W. Threlfall, MD

Medicare activity in 2024

Official CMS public-use data for Alexander W. Threlfall, 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.

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%
• Depression75%
• Anxiety75%
• High blood pressure65%

Hospitals where Alexander W. Threlfall works

Medicare's Facility Affiliation Data lists Alexander W. Threlfall 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.

• Marinhealth Medical CenterGreenbrae, CA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 050360

Practice locations

Addresses where Alexander W. Threlfall is enrolled with Medicare (CMS data updated October 2, 2026).

• 505 Parnassus AveSan Francisco, CA 94143 (415) 476‑1000
• 751 Lombardi CtSanta Rosa, CA 95407 (707) 303‑3600

Group practices

Medicare enrollment lists Alexander W. Threlfall as a member of these groups (CMS data updated October 2, 2026).

• Regents Univ of California UCSF283 clinicians in the group
• Santa Rosa Community Health Centers63 clinicians in the group

Specialties

• Psychiatryprimary
• Geriatric Psychiatryalso

Find other Psychiatry doctors in California →

Other psychiatrists in San Francisco

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

• Eduardo Garza, MD
• Gina M. Clark, MD
• Tova Fuller, MD
• Rebecca A. Clendenin, MD
• Daniel H. Mathalon, MD
• Pilar C. Abascal, MD
• Stephen C. Allison, MD
• Thomas L. Quirk, MD

All psychiatrists in San Francisco →

Other clinicians in Regents Univ of California UCSF

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

• Aileen K. Wang, MD
• Kristin A. Kline, AU
• Jayme Fellores
• Jonathan R. Goff, MD
• Willie Tang, MD
• Lauren A. Tipton, 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