Donald Siao, MD
NPI 1861415374 · Family Medicine Physician · San Jose, CA
Donald Siao, MD is a Family Medicine Physician provider in San Jose, CA (NPI 1861415374).
Provider details
- NPI number
- 1861415374
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- G73395 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
19 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
234 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 197 | $104 |
| Management Using the Results of Remote Vital Sign Monitoring Per Calendar Month, First 20 Minutes99457 | 21 | $59 |
| Established Patient Office Or Other Outpatient Visit With Straightforward Medical Decision Making, If Using Time, 10 Minutes Or More99212 | 16 | $69 |
Typical Medicare-allowed amounts for these services range $59–$104 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 43 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 159 | 96 |
| Amlodipine Besylate | 117 | 73 |
| Losartan Potassium | 114 | 71 |
| Metformin Hcl | 91 | 58 |
| Omeprazole | 60 | 35 |
| Lisinopril | 57 | 35 |
| Tamsulosin Hcl |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$675 across 26 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-07-25
- Last updated
- 2007-07-08
Frequently asked questions
- What is Donald Siao's NPI number?
- Donald Siao's National Provider Identifier (NPI) is 1861415374, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Donald Siao's specialty?
- Donald Siao is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Donald Siao located?
- Donald Siao's practice location on file with NPPES is 2690 S White Rd, San Jose, CA 95148-2076.
- What is Donald Siao's phone number?
- The practice phone number listed in the NPPES registry for Donald Siao is (408) 223-7771.
- Is Donald Siao's NPI active?
- Yes — Donald Siao's NPI (1861415374) is active in the NPPES registry as of the last update on 2007-07-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.