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Ann Ni, PA

Physician Assistant · Stanford

NPI 1871112607

Medicare standing
Clear
Enrolled, allowed to bill and order, not excluded
Plans that list them
Not verified
Not the same as out of network.
Office
1

Offices

1 location · 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.

Plan participation

Not verified

We could not verify current plan participation for this doctor. This does not mean they are out of network. Call Ann Ni’s office at (650) 723-4000 to ask if they take your plan before you enroll.

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

$5,279

Medicare paid this office $5,279 for 12 people.

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

Procedures Medicare counted

Procedure volume Medicare published
Melanoma (skin cancer) excision1-10None

Who their Medicare patients are

12 Original Medicare patients in 2024. Average age 71 · Under 65 0% · 85 and older 0% · Also on Medicaid 0% · Health risk score 0.88. At or below the middle of the specialty; the typical physician assistant clinician is at 1.31.

The office billed $312,080, Medicare allowed $6,527 and paid $5,279; for 42 services of 3 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
20241242710.88$312,080$5,279
202122101721.56$741,480$10,837

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

2021: 1 service

Original Medicare services billed in 2021
Creation of muscle graft to trunk18$9,068$130

Drugs they prescribed that Part D paid

$691

Pharmacies billed $691 in 2024.

This is pharmacy cost, not the office bill, and not what patients paid.

Opioids were 21% of their Part D prescriptions (25 of 120) in 2024. Above the middle of the specialty; the typical physician assistant clinician is at 1%.

118 generic and fewer than 11 brand-name prescriptions · $691 in drug cost · 39 antibiotic prescriptions to 24 people.

Part D prescriptions only. The opioid rate is opioid prescriptions as a share of all this clinician's Part D prescriptions; surgeons and pain specialists run higher than others, so it is shown against the same specialty.

Largest Part D drug costs
Ondansetron24$120$5
Cephalexin18$95$5
Chlorhexidine Gluconate15$90$6
Oxycodone-Acetaminophen22$90$4

Year by year

Part D prescribing by year
20241203521% (25)None$691
2023963017% (16)11%$4,261
202210032None33%$10,031
202110435None38%$12,164
20203415None41%$2,247

Part D prescriptions only. A drug prescribed to fewer than 11 people in a year is hidden.

See the drugs prescribed each year

2023: 4 drugs

Part D drugs prescribed in 2023
Gabapentin14$104$7
Ondansetron13$69$5
Oxycodone-Acetaminophen13$51$4
Cephalexin11$48$4

2022: 4 drugs

Part D drugs prescribed in 2022
Santyl11$8,941$813
Silver Sulfadiazine15$412$27
Chlorhexidine Gluconate15$65$4
Cephalexin12$31$3

2021: 4 drugs

Part D drugs prescribed in 2021
Santyl12$10,965$914
Silver Sulfadiazine25$938$38
Chlorhexidine Gluconate22$72$3
Cephalexin12$36$3

Money from drug and device companies

$1,691 in 2025

Industry payments by year
2025716None$1,691
2024824None$2,141
202358None$603
2022619None$2,274
2021612None$1,247

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
DavolPhasix Mesh$587
8 payments
  • Meals · 2025-06-19 · $14
  • Meals for Phasix Mesh · 2025-06-05 · $133
  • Meals · 2025-05-08 · $11
  • Meals · 2025-04-26 · $16
  • Meals for Phasix Mesh · 2025-04-11 · $155
  • Meals · 2025-03-05 · $16
  • Meals · 2025-02-19 · $22
  • Meals for Phasix Mesh · 2025-01-27 · $221
AtriCureAtriclip Laa Exclusion System$230
1 payment
  • Meals for Atriclip Laa Exclusion System · 2025-12-10 · $230
PolyNovo North AmericaNovosorb Btm$219
3 payments
  • Meals for Novosorb Btm · 2025-06-05 · $146
  • Meals for Novosorb Btm · 2025-05-29 · $33
  • Meals for Novosorb Btm · 2025-04-05 · $39
HeartflowFfrct$192
1 payment
  • Meals for Ffrct · 2025-10-23 · $192
W. L. Gore & AssociatesGore Enform Preperitoneal Biomaterial$175
1 payment
  • Meals for Gore Enform Preperitoneal Biomaterial · 2025-05-19 · $175
KerecisKerecis Surgiclose$150
1 payment
  • Meals for Kerecis Surgiclose · 2025-04-28 · $150
See all 16 published payments
Every published payment
AtriCureMeals · 2025-12-10Atriclip Laa Exclusion System$230
HeartflowMeals · 2025-10-23Ffrct$192
Getinge USA SalesMeals · 2025-08-22Vasoview Hemopro 2$139
DavolMeals · 2025-06-19None$14
DavolMeals · 2025-06-05Phasix Mesh$133
PolyNovo North AmericaMeals · 2025-06-05Novosorb Btm$146
PolyNovo North AmericaMeals · 2025-05-29Novosorb Btm$33
W. L. Gore & AssociatesMeals · 2025-05-19Gore Enform Preperitoneal Biomaterial$175
DavolMeals · 2025-05-08None$11
KerecisMeals · 2025-04-28Kerecis Surgiclose$150
DavolMeals · 2025-04-26None$16
DavolMeals · 2025-04-11Phasix Mesh$155
PolyNovo North AmericaMeals · 2025-04-05Novosorb Btm$39
DavolMeals · 2025-03-05None$16
DavolMeals · 2025-02-19None$22
DavolMeals · 2025-01-27Phasix Mesh$221
See earlier years (2024, 2023, 2022, 2021)

2024: $2,141

Payments by company in 2024
PolyNovo North AmericaNovosorb Btm$639
6 payments
  • Meals for Novosorb Btm · 2024-09-18 · $80
  • Meals for Novosorb Btm · 2024-09-04 · $124
  • Meals for Novosorb Btm · 2024-08-08 · $26
  • Meals for Novosorb Btm · 2024-07-11 · $189
  • Meals for Novosorb Btm · 2024-04-03 · $36
  • Meals for Novosorb Btm · 2024-04-01 · $185
DavolPhasix Mesh$372
4 payments
  • Meals for Phasix Mesh · 2024-12-19 · $48
  • Meals for Phasix Mesh · 2024-11-07 · $40
  • Meals for Phasix Mesh · 2024-10-30 · $59
  • Meals for Phasix Mesh · 2024-01-25 · $224
Musculoskeletal Transplant FoundationNone$328
4 payments
  • Meals · 2024-10-23 · $19
  • Meals · 2024-08-01 · $11
  • Meals · 2024-05-22 · $119
  • Meals · 2024-03-13 · $178
AbbvieAlloderm$282
3 payments
  • Meals for Alloderm · 2024-12-09 · $118
  • Meals for Alloderm · 2024-11-27 · $95
  • Meals for Alloderm · 2024-06-26 · $69
AxogenAvance Nerve Graft$209
3 payments
  • Meals for Avance Nerve Graft · 2024-11-27 · $86
  • Meals for Avance Nerve Graft · 2024-11-18 · $95
  • Meals for Avance Nerve Graft · 2024-06-26 · $28
KerecisKerecis Omega3 Surgiclose$158
2 payments
  • Meals for Kerecis Omega3 Surgiclose · 2024-10-15 · $107
  • Meals for Kerecis Omega3 Surgiclose · 2024-10-14 · $51
Integra LifeSciencesIntegra$107
1 payment
  • Meals for Integra · 2024-06-17 · $107
Becton Dickinson andPhasix Mesh$45
1 payment
  • Meals for Phasix Mesh · 2024-04-11 · $45

2023: $603

Payments by company in 2023
DavolPhasix Mesh$188
3 payments
  • Meals for Phasix Mesh · 2023-10-04 · $22
  • Meals for Phasix Mesh · 2023-09-27 · $20
  • Meals for Phasix Mesh · 2023-03-01 · $146
Becton Dickinson andPhasix Mesh$148
1 payment
  • Meals for Phasix Mesh · 2023-09-27 · $148
Avita Medical AmericasRecell$108
1 payment
  • Meals for Recell · 2023-11-06 · $108
Kci USAPrevena$103
2 payments
  • Meals for Prevena · 2023-10-02 · $76
  • Meals for Prevena · 2023-09-25 · $27
Mentor WorldwideMentor Cpx 2 Breast Tissue Expander$56
1 payment
  • Meals for Mentor Cpx 2 Breast Tissue Expander · 2023-04-11 · $56

2022: $2,274

Payments by company in 2022
SientraSientra High Strength Cohesive Silicone Gel Breast Implant$1,538
11 payments
  • Meals for Sientra High Strength Cohesive Silicone Gel Breast Implant · 2022-10-20 · $180
  • Meals for Sientra High Strength Cohesive Silicone Gel Breast Implant · 2022-10-19 · $165
  • Meals for Sientra High Strength Cohesive Silicone Gel Breast Implant · 2022-09-15 · $154
  • Meals for Sientra High Strength Cohesive Silicone Gel Breast Implant · 2022-06-30 · $176
  • Meals for Sientra High Strength Cohesive Silicone Gel Breast Implant · 2022-06-18 · $170
  • Meals for Sientra High Strength Cohesive Silicone Gel Breast Implant · 2022-06-16 · $165
  • Meals for Sientra High Strength Cohesive Silicone Gel Breast Implant · 2022-04-22 · $16
  • Meals for Sientra High Strength Cohesive Silicone Gel Breast Implant · 2022-04-21 · $20
  • Meals for Sientra High Strength Cohesive Silicone Gel Breast Implant · 2022-04-21 · $139
  • Meals for Sientra High Strength Cohesive Silicone Gel Breast Implant · 2022-03-30 · $174
  • Meals for Sientra High Strength Cohesive Silicone Gel Breast Implant · 2022-03-07 · $178
AxogenAvance Nerve Graft$245
3 payments
  • Meals for Avance Nerve Graft · 2022-08-01 · $120
  • Meals for Avance Nerve Graft · 2022-07-19 · $35
  • Meals for Avance Nerve Graft · 2022-06-01 · $89
Musculoskeletal Transplant FoundationNone$234
2 payments
  • Meals · 2022-11-23 · $59
  • Meals · 2022-11-02 · $175
DavolPhasix Mesh$165
1 payment
  • Meals for Phasix Mesh · 2022-09-28 · $165
Mentor WorldwideMentor Memorygel Resterilizable Gel Sizer$76
1 payment
  • Meals for Mentor Memorygel Resterilizable Gel Sizer · 2022-06-27 · $76
Kci USAPrevena$17
1 payment
  • Meals for Prevena · 2022-12-01 · $17

2021: $1,247

Payments by company in 2021
Biohaven PharmaceuticalsNurtec Odt$414
5 payments
  • Meals for Nurtec Odt · 2021-07-14 · $125
  • Meals for Nurtec Odt · 2021-05-05 · $65
  • Meals for Nurtec Odt · 2021-03-04 · $75
  • Meals for Nurtec Odt · 2021-02-18 · $74
  • Meals for Nurtec Odt · 2021-02-05 · $75
DavolProgel$292
2 payments
  • Meals for Progel · 2021-10-06 · $147
  • Meals for Phasix · 2021-10-04 · $145
Integra LifeSciencesIntegra Meshed Bilayer Wound Matrix$268
2 payments
  • Meals for Integra Meshed Bilayer Wound Matrix · 2021-08-02 · $143
  • Meals for Integra Meshed Bilayer Wound Matrix · 2021-07-08 · $125
AxogenAvance Nerve Graft$136
1 payment
  • Meals for Avance Nerve Graft · 2021-12-06 · $136
Mentor WorldwideArtoura Breast Tissue Expander$84
1 payment
  • Meals for Artoura Breast Tissue Expander · 2021-09-13 · $84
Medical Device Business ServicesStratafix$54
1 payment
  • Meals for Stratafix · 2021-02-17 · $54

Checkups this office reported

Medicare did not publish checkup rates for this clinician.

Medicare’s overall office score
100.0 / 100
Scores the office’s reporting and systems. It is not a grade for how the doctor treats you.

Professional record

NPI
1871112607
Video visits
Lists video visits
Gender
Female
More record details
Sole proprietor
No
Taxonomy
Physician assistant (363A00000X)
Mailing address
300 Pasteur Dr, Stanford, CA, 94305
NPI first listed
2020-04-12
NPI last updated
2025-08-04
NPI record certified
2025-08-04

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

Extra NPI addresses: 570 Lexington Ave Fl 9, New York, NY, 10022