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Yulia Zak, MD

General Practice · Redwood City

NPI 1720251333

Medicare standing
Clear
Enrolled, allowed to bill and order, not excluded
Plans that list them
13
2 carriers
Offices
3

Offices

3 locations · Stanford Health Care · 3,152 clinicians in this group

Looking this up.

Hospitals listed: Stanford Health Care. That is not proof they admit you there this week.

Plans that list them

13 plans · 2 carriers

A missing listing does not mean out of network. Directories change, and a listing does not cover every office. Call Dr. Zak’s office at (650) 723-4000 to confirm they take your plan. Ask about the office you use, its medical group, referrals and appointments.

13 of 13 plans

Plans whose provider directory lists this clinician
Alignment Health BreathEasy (HMO C-SNP)Alignment Health PlanListedOct 3, 2026
Alignment Health Clarity (HMO C-SNP)Alignment Health PlanListedOct 3, 2026
Alignment Health Harmony (HMO)Alignment Health PlanListedOct 3, 2026
Alignment Health Heart & Diabetes (HMO C-SNP)Alignment Health PlanListedOct 3, 2026
Alignment Health Heart & Diabetes CalPlus (HMO C-SNP)Alignment Health PlanListedOct 3, 2026
Alignment Health Heart & Diabetes Care (HMO C-SNP)Alignment Health PlanListedSep 28, 2026
Alignment Health Heart & Diabetes Choice (HMO C-SNP)Alignment Health PlanListedSep 28, 2026
Alignment Health Honor+ Plan (HMO)Alignment Health PlanListedOct 3, 2026
Alignment Health My Choice CalCare (HMO)Alignment Health PlanListedOct 3, 2026
Alignment Health Silicon (HMO C-SNP)Alignment Health PlanListedOct 3, 2026
Alignment Health smartHMO (HMO)Alignment Health PlanListedOct 3, 2026
Alignment Health the ONE (HMO)Alignment Health PlanListedOct 3, 2026
DualConnect (HMO D-SNP)Santa Clara Family Health PlanListedSep 1, 2026

California Medical Board record

Licence A113665 · Current

Licensed to practise in California · since 2010 · expires 2027-12-31 · State University of New York Health Science Center at Brooklyn.

No disciplinary actions, convictions, malpractice judgments or citations in this record.

Hospitals they work in

1 hospital

These rate the hospital, not this clinician. Most measures at most hospitals are no different from the national rate.

  • Stanford Health CareStanford, CAAcute Care Hospital · Voluntary non-profit - Private · Has an emergency departmentPart of Stanford Health Care, which runs 3 hospitalsHome of Stanford Cancer Institute, a National Cancer Institute designated comprehensive cancer centrePatients rate it 4 of 5 · 83% would definitely recommend it
    Overall rating: 5 of 5 starsWorse than the national rate — Perioperative pulmonary embolism or deep vein thrombosis rate: 5.31 (4.24 to 6.37) · 8,661 cases, Jul 2022 – Jun 2024Worse than the national rate — Rate of inpatient admissions for patients receiving outpatient chemotherapy: 14.1 (12.7 to 15.7) · 2,191 cases, Jan 2024 – Dec 2024Better than the national rate — Postoperative respiratory failure rate: 4.08 (1.95 to 6.21) · 5,296 cases, Jul 2022 – Jun 2024Better than the national rate — Catheter Associated Urinary Tract Infections (ICU + select Wards): 0.317, Oct 2024 – Sep 2025Better than the national rate — Clostridium Difficile (C.Diff): 0.446, Oct 2024 – Sep 2025Better than the national rate — SSI - Colon Surgery: 0.241, Oct 2024 – Sep 2025Better than the national rate — Ratio of unplanned hospital visits after hospital outpatient surgery: 0.7 (0.6 to 0.9) · 3,348 cases, Jan 2024 – Dec 2024
See every measure and the patient survey for Stanford Health Care

Behind the star rating — Deaths: 5 better, 3 the same, 0 worse of 8 measures. Safety: 3 better, 5 the same, 0 worse of 8 measures. Readmissions: 2 better, 5 the same, 4 worse of 11 measures. The star rating is worked out from an earlier period than the measures below, so the two can disagree.

Every scored measure at Stanford Health Care
Perioperative pulmonary embolism or deep vein thrombosis rateComplications and deaths5.31 (4.24 to 6.37) · 8,661 casesWorseJul 2022 – Jun 2024
Rate of inpatient admissions for patients receiving outpatient chemotherapyUnplanned return visits14.1 (12.7 to 15.7) · 2,191 casesWorseJan 2024 – Dec 2024
Postoperative respiratory failure rateComplications and deaths4.08 (1.95 to 6.21) · 5,296 casesBetterJul 2022 – Jun 2024
Catheter Associated Urinary Tract Infections (ICU + select Wards)Infections0.317BetterOct 2024 – Sep 2025
Clostridium Difficile (C.Diff)Infections0.446BetterOct 2024 – Sep 2025
SSI - Colon SurgeryInfections0.241BetterOct 2024 – Sep 2025
Ratio of unplanned hospital visits after hospital outpatient surgeryUnplanned return visits0.7 (0.6 to 0.9) · 3,348 casesBetterJan 2024 – Dec 2024
Abdominopelvic accidental puncture or laceration rateComplications and deaths1.06 (0.45 to 1.67) · 5,374 casesNo differentJul 2022 – Jun 2024
CMS Medicare PSI 90: Patient safety and adverse events compositeComplications and deaths0.86 (0.72 to 1)No differentJul 2022 – Jun 2024
Death rate among surgical inpatients with serious treatable complicationsComplications and deaths166.09 (137.88 to 194.3) · 470 casesNo differentJul 2022 – Jun 2024
Death rate for CABG surgery patientsComplications and deaths1.1 · 192 casesNoneJul 2022 – Jun 2025
Death rate for COPD patientsComplications and deaths6.4 · 146 casesNoneJul 2022 – Jun 2025
Death rate for heart attack patientsComplications and deaths9.7 · 253 casesNoneJul 2022 – Jun 2025
Death rate for heart failure patientsComplications and deaths6.3 · 880 casesNoneJul 2022 – Jun 2025
Death rate for pneumonia patientsComplications and deaths10.3 · 935 casesNoneJul 2022 – Jun 2025
Death rate for stroke patientsComplications and deaths8.7 · 501 casesNoneJul 2023 – Jun 2025
Hybrid Hospital-Wide All-Cause Risk Standardized Mortality RateComplications and deaths2.1 · 7,730 casesNoneJul 2024 – Jun 2025
Iatrogenic pneumothorax rateComplications and deaths0.13 (0 to 0.27) · 20,799 casesNo differentJul 2022 – Jun 2024
In-hospital fall-associated fracture rateComplications and deaths0.28 (0.14 to 0.43) · 23,182 casesNo differentJul 2022 – Jun 2024
Postoperative acute kidney injury requiring dialysis rateComplications and deaths0.94 (0.2 to 1.68) · 5,694 casesNo differentJul 2022 – Jun 2024
Postoperative hemorrhage or hematoma rateComplications and deaths2.36 (1.54 to 3.19) · 7,846 casesNo differentJul 2022 – Jun 2024
Postoperative sepsis rateComplications and deaths5.2 (3.76 to 6.64) · 5,603 casesNo differentJul 2022 – Jun 2024
Postoperative wound dehiscence rateComplications and deaths1.38 (0.23 to 2.53) · 2,211 casesNo differentJul 2022 – Jun 2024
Pressure ulcer rateComplications and deaths0.52 (0.21 to 0.83) · 19,915 casesNo differentJul 2022 – Jun 2024
Rate of complications for hip/knee replacement patientsComplications and deaths3.6 · 416 casesNoneApr 2023 – Mar 2025
Central Line Associated Bloodstream Infection (ICU + select Wards)Infections0.869No differentOct 2024 – Sep 2025
MRSA BacteremiaInfections0.857No differentOct 2024 – Sep 2025
SSI - Abdominal HysterectomyInfections0.368No differentOct 2024 – Sep 2025
Acute Myocardial Infarction (AMI) 30-Day Readmission RateUnplanned return visits16.2 · 247 casesNoneJul 2023 – Jun 2025
Heart failure (HF) 30-Day Readmission RateUnplanned return visits20.5 · 1,021 casesNoneJul 2023 – Jun 2025
Hospital return days for heart attack patientsUnplanned return visits47.8 · 258 casesNoneJul 2022 – Jun 2025
Hospital return days for heart failure patientsUnplanned return visits-1.6 · 990 casesNoneJul 2022 – Jun 2025
Hospital return days for pneumonia patientsUnplanned return visits20.8 · 976 casesNoneJul 2022 – Jun 2025
Pneumonia (PN) 30-Day Readmission RateUnplanned return visits16.5 · 959 casesNoneJul 2023 – Jun 2025
Rate of emergency department (ED) visits for patients receiving outpatient chemotherapyUnplanned return visits5.2 (4.4 to 6.2) · 2,191 casesNo differentJan 2024 – Dec 2024
Rate of readmission after hip/knee replacementUnplanned return visits5.1 · 425 casesNoneJul 2023 – Jun 2025
Rate of readmission for CABGUnplanned return visits9.6 · 158 casesNoneJul 2023 – Jun 2025
Rate of readmission for chronic obstructive pulmonary disease (COPD) patientsUnplanned return visits19.6 · 183 casesNoneJul 2023 – Jun 2025
Rate of unplanned hospital visits after colonoscopy (per 1,000 colonoscopies)Unplanned return visits12.7 (10.4 to 15.4) · 4,578 casesNo differentJan 2022 – Dec 2024

What patients said (6,810 patients answered, 25% of those asked)

Patient survey stars by topic at Stanford Health Care
Cleanliness4
Nurse communication4
Doctor communication4
Communication about medicines3
Discharge information4
Overall hospital rating4
Quietness2
Recommend hospital5
Share of patients giving the best answer at Stanford Health Care
Room was "always" clean75%
Nurses "always" communicated well82%
Doctors "always" communicated well81%
Staff "always" explained63%
Yes, staff "did" give patients this information89%
Yes, staff "did" give patients information about help after discharge89%
Doctors "always" explained things so they could understand76%
Doctors "always" listened carefully80%
Doctors "always" treated them with courtesy and respect87%
Patients who gave a rating of "9" or "10" (high)79%
Staff "always" explained new medications76%
Nurses "always" explained things so they could understand77%
Nurses "always" listened carefully79%
Nurses "always" treated them with courtesy and respect88%
"Always" quiet at night53%
"YES", patients would definitely recommend the hospital83%
Staff "always" explained possible side effects50%
Yes, staff "did" give patients information about possible symptoms90%

Original Medicare doctor bills

$27,447

Medicare paid this office $27,447 for 70 people. Most of that is long return visits and Botox.

This is what Medicare paid the clinician — not Medicare Advantage, and not the pharmacy.

Largest Original Medicare bills
Long return visit (40+ min)22$4,134$159
New patient visit (45+ min)14$1,857$133
Return visit (30+ min)14$1,364$97
New patient visit (30+ min)11$725$66

Procedures Medicare counted

Procedure volume Medicare published
Hernia repair - groin (open)1-10None
Hernia repair (minimally invasive)15More than 82% of doctors who do this
Upper gastrointestinal (GI) endoscopy for acid reflux1-10None

Who their Medicare patients are

70 Original Medicare patients in 2024. Average age 70 · Women 57% · Also on Medicaid 33% · Health risk score 1.59. Above the middle of the specialty; the typical general practice clinician is at 1.33.

Conditions among them: High blood pressure 71% · Diabetes 34% · Depression 30% · Chronic kidney disease 26% · Cancer 23% · Coronary heart disease 16% · Heart failure 16% · Atrial fibrillation 16%.

The office billed $152,113, Medicare allowed $34,616 and paid $27,447; for 108 services of 25 kinds.

Original Medicare patients only. A risk score of 1.0 is the average Medicare patient; higher means sicker. Any count under 11 is hidden.

Year by year

Original Medicare by year
202470108701.59$152,113$27,447
202368116651.66$107,123$17,474
20224265612.11$61,109$10,288
2021109193681.72$222,582$38,799
2020103174681.63$167,651$31,753
2019110187682.20$136,505$29,566
20183563611.55$66,742$10,427
20172855612.27$53,027$8,350
201636115611.82$83,720$15,835
20153755641.58$53,978$9,289
20143848641.20$44,318$6,518

Original Medicare only. A service billed for fewer than 11 people in a year is hidden, so the lines can add up to less than the year's total.

See the services billed each year

2023: 2 services

Original Medicare services billed in 2023
Return visit (30+ min)14$1,213$87
New patient visit (30+ min)14$991$71

2021: 5 services

Original Medicare services billed in 2021
New patient visit (60+ min)12$2,106$175
New patient visit (30+ min)22$1,702$77
Return visit (30+ min)17$1,701$100
New patient visit (45+ min)12$1,576$131
Short return visit (20+ min)15$1,221$61

2020: 5 services

Original Medicare services billed in 2020
New patient visit (30+ min)26$1,754$67
Initial hospital care with straightforward or low-level medical decision making at least 55 minutes12$1,517$126
New patient visit (45+ min)11$999$91
Short return visit (20+ min)11$573$48
Short return visit (20+ min)11$495$45

2019: 3 services

Original Medicare services billed in 2019
New patient visit (45+ min)22$2,535$115
New patient visit (45+ min)18$2,095$116
New patient visit (30+ min)24$1,574$66

2018: 1 service

Original Medicare services billed in 2018
Short return visit (20+ min)18$922$35

2016: 2 services

Original Medicare services billed in 2016
New patient visit (45+ min)12$1,391$116
Short return visit11$1,090$24

Medicaid work

$2,159 in 2024

Medicaid paid $2,159 for 12 billed services this clinician did in 2024, up to 12 people in a month for one service.

Medicaid and CHIP claims where this clinician did the service, fee-for-service and managed care together. Any month with fewer than 11 patients is hidden, so small Medicaid practices undercount.

Largest Medicaid services in 2024
New patient visit (60+ min)12$2,159
Medicaid work by year
202412112$2,159
202228115$1,389
202154314$2,553
202041115$966
201858117$3,014
See the largest Medicaid services in earlier years

2022

Largest Medicaid services in 2022
Long return visit (40+ min)28$1,389

2021

Largest Medicaid services in 2021
New patient visit (60+ min)14$1,427
Return visit (30+ min)26$835
Short return visit (20+ min)14$290

2020

Largest Medicaid services in 2020
Short return visit (20+ min)41$966

2018

Largest Medicaid services in 2018
Short return visit (20+ min)58$3,014

Money from drug and device companies

$327 in 2025

Industry payments by year
202525None$327
202311None$3,000
202213None$3,023
202015None$4,112
201915None$117

Paid work is consulting, speaking, honoraria and royalties, as opposed to meals and travel.

A payment is not proof that care is biased.

Payments by company
TeleflexTitan Sgs Bailout Chuck$198
4 payments
  • Meals for Titan Sgs Bailout Chuck · 2025-04-12 · $122
  • Meals for Titan Sgs Bailout Chuck · 2025-04-01 · $40
  • Meals for Titan Sgs Bailout Chuck · 2025-03-28 · $24
  • Meals for Titan Sgs Bailout Chuck · 2025-03-28 · $13
MedtronicSignia$129
1 payment
  • Meals for Signia · 2025-04-12 · $129
See all 5 published payments
Every published payment
MedtronicMeals · 2025-04-12Signia$129
TeleflexMeals · 2025-04-12Titan Sgs Bailout Chuck$122
TeleflexMeals · 2025-04-01Titan Sgs Bailout Chuck$40
TeleflexMeals · 2025-03-28Titan Sgs Bailout Chuck$24
TeleflexMeals · 2025-03-28Titan Sgs Bailout Chuck$13
See earlier years (2023, 2022, 2020, 2019)

2023: $3,000

Payments by company in 2023
Intuitive SurgicalDavinci Xi$3,000
1 payment
  • Education for Davinci Xi · 2023-03-06 · $3,000

2022: $3,023

Payments by company in 2022
Intuitive SurgicalDavinci Xi$3,023
3 payments
  • Meals for Da Vinci Surgical System · 2022-12-20 · $5
  • Meals for Da Vinci Surgical System · 2022-09-27 · $18
  • Education for Davinci Xi · 2022-08-15 · $3,000

2020: $4,112

Payments by company in 2020
Intuitive SurgicalDa Vinci Surgical System$4,112
5 payments
  • Education for Da Vinci Surgical System · 2020-09-29 · $3,000
  • Meals for Da Vinci Surgical System · 2020-09-11 · $26
  • Education for Da Vinci Surgical System · 2020-09-11 · $1,000
  • Meals for Da Vinci Surgical System · 2020-01-21 · $22
  • Meals for Da Vinci Surgical System · 2020-01-21 · $64

2019: $117

Payments by company in 2019
Intuitive SurgicalDa Vinci Surgical System$117
5 payments
  • Meals for Da Vinci Surgical System · 2019-07-06 · $6
  • Meals for Da Vinci Surgical System · 2019-07-06 · $8
  • Meals for Da Vinci Surgical System · 2019-07-06 · $52
  • Meals for Da Vinci Surgical System · 2019-06-27 · $13
  • Meals for Da Vinci Surgical System · 2019-05-02 · $39

Professional record

NPI
1720251333
Licence
CA A113665, MA 257922, NY 279543California A113665: Current · expires 2027-12-31
Video visits
Lists video visits
Gender
Female
More record details
Sole proprietor
No
Taxonomy
Surgery (208600000X)
Mailing address
300 Pasteur Dr, Palo Alto, CA, 94304
NPI first listed
2008-04-04
NPI last updated
2024-04-29
NPI record certified
2024-04-29

This is when the NPI record was last certified, not a medical board exam.