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Sheri Ann Loo, NP

Nurse Practitioner · Stanford

NPI 1932627221

Medicare standing
Clear
Enrolled, allowed to bill and order, not excluded
Plans that list them
Not verified
Not the same as out of network.
Offices
2

Offices

2 locations · Stanford Health Care · David B. Hammer

Looking this up.

Hospitals listed: Stanford Health Care · Stanford Health Care Tri-Valley. 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 Sheri Ann Loo’s office at (650) 723-4000 to ask if they take your plan before you enroll.

Hospitals they work in

2 hospitals

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
  • Stanford Health Care Tri-ValleyPleasanton, CAAcute Care Hospital · Voluntary non-profit - Private · Has an emergency department · Birthing-friendlyPart of Stanford Health Care, which runs 3 hospitalsPatients rate it 3 of 5 · 74% would definitely recommend it
    Overall rating: 5 of 5 starsBetter than the national rate — Central Line Associated Bloodstream Infection (ICU + select Wards): 0.178, Oct 2024 – Sep 2025Better than the national rate — Clostridium Difficile (C.Diff): 0.237, Oct 2024 – Sep 2025
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%
See every measure and the patient survey for Stanford Health Care Tri-Valley

Behind the star rating — Deaths: 2 better, 6 the same, 0 worse of 8 measures. Safety: 2 better, 5 the same, 0 worse of 7 measures. Readmissions: 2 better, 7 the same, 0 worse of 9 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 Tri-Valley
Central Line Associated Bloodstream Infection (ICU + select Wards)Infections0.178BetterOct 2024 – Sep 2025
Clostridium Difficile (C.Diff)Infections0.237BetterOct 2024 – Sep 2025
Abdominopelvic accidental puncture or laceration rateComplications and deaths0.79 (0 to 1.73) · 1,041 casesNo differentJul 2022 – Jun 2024
CMS Medicare PSI 90: Patient safety and adverse events compositeComplications and deaths0.79 (0.5 to 1.08)No differentJul 2022 – Jun 2024
Death rate among surgical inpatients with serious treatable complicationsComplications and deaths145.81 (96.5 to 195.12) · 72 casesNo differentJul 2022 – Jun 2024
Death rate for CABG surgery patientsComplications and deaths2.9 · 55 casesNoneJul 2022 – Jun 2025
Death rate for COPD patientsComplications and deaths8.6 · 92 casesNoneJul 2022 – Jun 2025
Death rate for heart attack patientsComplications and deaths12.5 · 96 casesNoneJul 2022 – Jun 2025
Death rate for heart failure patientsComplications and deaths9.5 · 395 casesNoneJul 2022 – Jun 2025
Death rate for pneumonia patientsComplications and deaths10.3 · 391 casesNoneJul 2022 – Jun 2025
Death rate for stroke patientsComplications and deaths10.1 · 162 casesNoneJul 2023 – Jun 2025
Hybrid Hospital-Wide All-Cause Risk Standardized Mortality RateComplications and deaths3 · 1,736 casesNoneJul 2024 – Jun 2025
Iatrogenic pneumothorax rateComplications and deaths0.16 (0 to 0.37) · 4,425 casesNo differentJul 2022 – Jun 2024
In-hospital fall-associated fracture rateComplications and deaths0.22 (0.02 to 0.41) · 4,771 casesNo differentJul 2022 – Jun 2024
Perioperative pulmonary embolism or deep vein thrombosis rateComplications and deaths3.45 (1.46 to 5.44) · 1,403 casesNo differentJul 2022 – Jun 2024
Postoperative acute kidney injury requiring dialysis rateComplications and deaths1.5 (0.05 to 2.94) · 645 casesNo differentJul 2022 – Jun 2024
Postoperative hemorrhage or hematoma rateComplications and deaths1.81 (0.38 to 3.24) · 1,279 casesNo differentJul 2022 – Jun 2024
Postoperative respiratory failure rateComplications and deaths8.53 (3.2 to 13.85) · 639 casesNo differentJul 2022 – Jun 2024
Postoperative sepsis rateComplications and deaths5.15 (1.89 to 8.41) · 648 casesNo differentJul 2022 – Jun 2024
Postoperative wound dehiscence rateComplications and deaths1.61 (0.14 to 3.07) · 370 casesNo differentJul 2022 – Jun 2024
Pressure ulcer rateComplications and deaths0.16 (0 to 0.83) · 4,160 casesNo differentJul 2022 – Jun 2024
Rate of complications for hip/knee replacement patientsComplications and deaths4 · 74 casesNoneApr 2023 – Mar 2025
Catheter Associated Urinary Tract Infections (ICU + select Wards)Infections0.369No differentOct 2024 – Sep 2025
MRSA BacteremiaInfections1.112No differentOct 2024 – Sep 2025
SSI - Colon SurgeryInfections0No differentOct 2024 – Sep 2025
Acute Myocardial Infarction (AMI) 30-Day Readmission RateUnplanned return visits13.1 · 110 casesNoneJul 2023 – Jun 2025
Heart failure (HF) 30-Day Readmission RateUnplanned return visits20.1 · 437 casesNoneJul 2023 – Jun 2025
Hospital return days for heart attack patientsUnplanned return visits-5.8 · 94 casesNoneJul 2022 – Jun 2025
Hospital return days for heart failure patientsUnplanned return visits-19.3 · 456 casesNoneJul 2022 – Jun 2025
Hospital return days for pneumonia patientsUnplanned return visits-0.3 · 402 casesNoneJul 2022 – Jun 2025
Pneumonia (PN) 30-Day Readmission RateUnplanned return visits15.8 · 358 casesNoneJul 2023 – Jun 2025
Rate of emergency department (ED) visits for patients receiving outpatient chemotherapyUnplanned return visits6.8 (4.7 to 9.6) · 198 casesNo differentJan 2024 – Dec 2024
Rate of inpatient admissions for patients receiving outpatient chemotherapyUnplanned return visits10.1 (7.5 to 13.6) · 198 casesNo differentJan 2024 – Dec 2024
Rate of readmission after hip/knee replacementUnplanned return visits5.3 · 80 casesNoneJul 2023 – Jun 2025
Rate of readmission for CABGUnplanned return visits10.9 · 46 casesNoneJul 2023 – Jun 2025
Rate of readmission for chronic obstructive pulmonary disease (COPD) patientsUnplanned return visits19.3 · 92 casesNoneJul 2023 – Jun 2025
Rate of unplanned hospital visits after colonoscopy (per 1,000 colonoscopies)Unplanned return visits12.4 (9.6 to 16.2) · 1,532 casesNo differentJan 2022 – Dec 2024
Ratio of unplanned hospital visits after hospital outpatient surgeryUnplanned return visits1 (0.8 to 1.2) · 929 casesNo differentJan 2024 – Dec 2024

What patients said (1,268 patients answered, 26% of those asked)

Patient survey stars by topic at Stanford Health Care Tri-Valley
Cleanliness3
Nurse communication3
Doctor communication4
Communication about medicines3
Discharge information4
Overall hospital rating3
Quietness2
Recommend hospital4
Share of patients giving the best answer at Stanford Health Care Tri-Valley
Room was "always" clean65%
Nurses "always" communicated well77%
Doctors "always" communicated well79%
Staff "always" explained58%
Yes, staff "did" give patients this information88%
Yes, staff "did" give patients information about help after discharge88%
Doctors "always" explained things so they could understand74%
Doctors "always" listened carefully78%
Doctors "always" treated them with courtesy and respect86%
Patients who gave a rating of "9" or "10" (high)70%
Staff "always" explained new medications72%
Nurses "always" explained things so they could understand73%
Nurses "always" listened carefully74%
Nurses "always" treated them with courtesy and respect84%
"Always" quiet at night42%
"YES", patients would definitely recommend the hospital74%
Staff "always" explained possible side effects44%
Yes, staff "did" give patients information about possible symptoms89%

Original Medicare doctor bills

$9,174

Medicare paid this office $9,174 for 106 people.

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

Largest Original Medicare bills
Short return visit (20+ min)44$3,380$72
Telephone medical discussion with physician, 21-30 minutes18$1,899$106
Return visit (30+ min)12$1,123$94
Telephone medical discussion with physician, 11-20 minutes11$827$69

Who their Medicare patients are

106 Original Medicare patients in 2024. Average age 72 · Women 57% · Also on Medicaid 28% · Health risk score 1.98. Above the middle of the specialty; the typical nurse practitioner clinician is at 1.42.

Conditions among them: High blood pressure 75% · Depression 35% · Diabetes 30% · Coronary heart disease 30% · Chronic kidney disease 26% · Heart failure 21% · Atrial fibrillation 20% · Cancer 16% · COPD 14% · Stroke 13% · Dementia 10%.

The office billed $58,861, Medicare allowed $12,175 and paid $9,174; for 123 services of 10 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
2024106123721.98$58,861$9,174
20235869731.53$25,884$3,498
20226065711.22$26,598$3,764

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: 1 service

Original Medicare services billed in 2023
Short return visit (20+ min)33$1,763$49

2022: 1 service

Original Medicare services billed in 2022
Short return visit (20+ min)27$1,447$52

Drugs they prescribed that Part D paid

$2,293

Pharmacies billed $2,293 in 2024.

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

Opioids were 43% of their Part D prescriptions (60 of 140) in 2024. A higher opioid share than 9 in 10 peers; the typical nurse practitioner clinician is at 0%.

137 generic and fewer than 11 brand-name prescriptions · $2,293 in drug cost.

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
Oxycodone23$400$9
Cyclobenzaprine11$99$6

Year by year

Part D prescribing by year
20241405643% (60)None$2,293
20231286734% (43)None$1,458
20221156145% (52)None$1,684
20211055739% (41)None$1,563
20201195342% (50)None$1,539
2019824642% (34)None$1,764
2018361956% (20)0%$333

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

See the drugs prescribed each year

2023: 3 drugs

Part D drugs prescribed in 2023
Oxycodone36$342$10
Cyclobenzaprine15$239$16
Gabapentin18$211$12

2022: 4 drugs

Part D drugs prescribed in 2022
Oxycodone35$385$11
Cyclobenzaprine11$137$12
Hydrocodone-Acetaminophen15$133$9
Gabapentin21$117$6

2021: 1 drug

Part D drugs prescribed in 2021
Oxycodone29$215$7

2020: 2 drugs

Part D drugs prescribed in 2020
Oxycodone37$440$12
Cyclobenzaprine22$117$5

2019: 3 drugs

Part D drugs prescribed in 2019
Hydrocodone-Acetaminophen15$211$14
Gabapentin14$177$13
Oxycodone15$137$9

2018: 1 drug

Part D drugs prescribed in 2018
Oxycodone14$163$12

Money from drug and device companies

$343 in 2025

Industry payments by year
202533None$343
202433None$368
202377None$854
202244None$453
202111None$49

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
Argenx USVyvgart$122
1 payment
  • Meals for Vyvgart · 2025-05-14 · $122
Amarin PharmaVascepa$118
1 payment
  • Meals for Vascepa · 2025-03-14 · $118
Corcept TherapeuticsKorlym$103
1 payment
  • Meals for Korlym · 2025-01-08 · $103
See all 3 published payments
Every published payment
Argenx USMeals · 2025-05-14Vyvgart$122
Amarin PharmaMeals · 2025-03-14Vascepa$118
Corcept TherapeuticsMeals · 2025-01-08Korlym$103
See earlier years (2024, 2023, 2022, 2021)

2024: $368

Payments by company in 2024
Edwards LifesciencesEdwards Sapien 3 Transcatheter Heart Valve (Thv)$168
1 payment
  • Meals for Edwards Sapien 3 Transcatheter Heart Valve (Thv) · 2024-09-12 · $168
BiogenSpinraza$122
1 payment
  • Meals for Spinraza · 2024-07-10 · $122
Evofem BiosciencesNone$78
1 payment
  • Meals · 2024-03-13 · $78

2023: $854

Payments by company in 2023
Averitas PharmaQutenza$130
1 payment
  • Meals for Qutenza · 2023-07-12 · $130
ItiCaplyta$126
1 payment
  • Meals for Caplyta · 2023-02-08 · $126
Gilead SciencesEpclusa$124
1 payment
  • Meals for Epclusa · 2023-04-26 · $124
Mayne Pharma CommercialNextstellis$124
1 payment
  • Meals for Nextstellis · 2023-07-11 · $124
NuVasiveAttrax$122
1 payment
  • Meals for Attrax · 2023-05-31 · $122
AmgenEvenity$118
1 payment
  • Meals for Evenity · 2023-03-30 · $118
AbbvieVraylar$111
1 payment
  • Meals for Vraylar · 2023-01-18 · $111

2022: $453

Payments by company in 2022
Vertos MedicalMild Device Kit$128
1 payment
  • Meals for Mild Device Kit · 2022-02-16 · $128
AmgenRepatha$125
1 payment
  • Meals for Repatha · 2022-08-10 · $125
Otsuka Pharmaceutical Development & CommercializationJynarque$111
1 payment
  • Meals for Jynarque · 2022-08-18 · $111
ScynexisNone$88
1 payment
  • Meals · 2022-04-21 · $88

2021: $49

Payments by company in 2021
Biohaven PharmaceuticalsNurtec Odt$49
1 payment
  • Meals for Nurtec Odt · 2021-03-25 · $49

Checkups this office reported

Medicare did not publish checkup rates for this clinician.

Medicare’s overall office score
76.5 / 100
Scores the office’s reporting and systems. It is not a grade for how the doctor treats you.

Professional record

NPI
1932627221
Licence
CA 95007282
Group
Stanford Health Care · David B. Hammer
Video visits
Lists video visits
Gender
Female
More record details
Sole proprietor
No
Taxonomy
Nurse practitioner (363L00000X); Federal specialty code 363LA2200X (363LA2200X)
Mailing address
300 Pasteur Dr, Stanford, CA, 94305
NPI first listed
2017-09-06
NPI last updated
2025-12-30
NPI record certified
2025-12-30

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