Benjamin Chang, MD
Hospitalist · Los Altos
- 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 · Sutter Bay Medical Foundation · 3,783 clinicians in this group
Looking this up.
Hospitals listed: El Camino Health. 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 Dr. Chang’s office at (650) 254-5200 to ask if they take your plan before you enroll.
California Medical Board record
Licence A70755 · Current
Licensed to practise in California · since 2000 · expires 2028-01-31 · University of Michigan Medical School.
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.
- El Camino HealthMountain View, CAAcute Care Hospital · Government - Hospital District or Authority · Has an emergency department · Birthing-friendlyPart of El Camino Health, which runs 2 hospitalsPatients rate it 4 of 5 · 80% would definitely recommend itOverall rating: 4 of 5 starsBetter than the national rate — Central Line Associated Bloodstream Infection (ICU + select Wards): 0.291, Oct 2024 – Sep 2025Better than the national rate — Clostridium Difficile (C.Diff): 0.393, Oct 2024 – Sep 2025Better than the national rate — MRSA Bacteremia: 0, Oct 2024 – Sep 2025
See every measure and the patient survey for El Camino Health
Behind the star rating — Deaths: 3 better, 5 the same, 0 worse of 8 measures. Safety: 3 better, 5 the same, 0 worse of 8 measures. Readmissions: 1 better, 9 the same, 1 worse of 11 measures. The star rating is worked out from an earlier period than the measures below, so the two can disagree.
| Central Line Associated Bloodstream Infection (ICU + select Wards)Infections | 0.291 | Better | Oct 2024 – Sep 2025 |
| Clostridium Difficile (C.Diff)Infections | 0.393 | Better | Oct 2024 – Sep 2025 |
| MRSA BacteremiaInfections | 0 | Better | Oct 2024 – Sep 2025 |
| Abdominopelvic accidental puncture or laceration rateComplications and deaths | 0.96 (0.12 to 1.79) · 2,340 cases | No different | Jul 2022 – Jun 2024 |
| CMS Medicare PSI 90: Patient safety and adverse events compositeComplications and deaths | 1.02 (0.76 to 1.28) | No different | Jul 2022 – Jun 2024 |
| Death rate among surgical inpatients with serious treatable complicationsComplications and deaths | 167.38 (125.03 to 209.73) · 96 cases | No different | Jul 2022 – Jun 2024 |
| Death rate for CABG surgery patientsComplications and deaths | 2.6 · 68 cases | None | Jul 2022 – Jun 2025 |
| Death rate for COPD patientsComplications and deaths | 7.1 · 185 cases | None | Jul 2022 – Jun 2025 |
| Death rate for heart attack patientsComplications and deaths | 11.8 · 200 cases | None | Jul 2022 – Jun 2025 |
| Death rate for heart failure patientsComplications and deaths | 8.9 · 814 cases | None | Jul 2022 – Jun 2025 |
| Death rate for pneumonia patientsComplications and deaths | 13 · 842 cases | None | Jul 2022 – Jun 2025 |
| Death rate for stroke patientsComplications and deaths | 9.6 · 361 cases | None | Jul 2023 – Jun 2025 |
| Hybrid Hospital-Wide All-Cause Risk Standardized Mortality RateComplications and deaths | 2.6 · 4,633 cases | None | Jul 2024 – Jun 2025 |
| Iatrogenic pneumothorax rateComplications and deaths | 0.16 (0 to 0.34) · 11,474 cases | No different | Jul 2022 – Jun 2024 |
| In-hospital fall-associated fracture rateComplications and deaths | 0.27 (0.1 to 0.45) · 11,626 cases | No different | Jul 2022 – Jun 2024 |
| Perioperative pulmonary embolism or deep vein thrombosis rateComplications and deaths | 3.14 (1.39 to 4.9) · 2,814 cases | No different | Jul 2022 – Jun 2024 |
| Postoperative acute kidney injury requiring dialysis rateComplications and deaths | 2 (0.61 to 3.39) · 1,327 cases | No different | Jul 2022 – Jun 2024 |
| Postoperative hemorrhage or hematoma rateComplications and deaths | 2.11 (0.8 to 3.43) · 2,641 cases | No different | Jul 2022 – Jun 2024 |
| Postoperative respiratory failure rateComplications and deaths | 9.39 (4.18 to 14.6) · 1,287 cases | No different | Jul 2022 – Jun 2024 |
| Postoperative sepsis rateComplications and deaths | 6.57 (3.47 to 9.68) · 1,308 cases | No different | Jul 2022 – Jun 2024 |
| Postoperative wound dehiscence rateComplications and deaths | 2.14 (0.71 to 3.57) · 827 cases | No different | Jul 2022 – Jun 2024 |
| Pressure ulcer rateComplications and deaths | 0.6 (0.05 to 1.15) · 9,460 cases | No different | Jul 2022 – Jun 2024 |
| Rate of complications for hip/knee replacement patientsComplications and deaths | 4.5 · 122 cases | None | Apr 2023 – Mar 2025 |
| Catheter Associated Urinary Tract Infections (ICU + select Wards)Infections | 0.993 | No different | Oct 2024 – Sep 2025 |
| SSI - Abdominal HysterectomyInfections | 0.706 | No different | Oct 2024 – Sep 2025 |
| SSI - Colon SurgeryInfections | 1.376 | No different | Oct 2024 – Sep 2025 |
| Acute Myocardial Infarction (AMI) 30-Day Readmission RateUnplanned return visits | 15.5 · 218 cases | None | Jul 2023 – Jun 2025 |
| Heart failure (HF) 30-Day Readmission RateUnplanned return visits | 19.5 · 962 cases | None | Jul 2023 – Jun 2025 |
| Hospital return days for heart attack patientsUnplanned return visits | 3.8 · 200 cases | None | Jul 2022 – Jun 2025 |
| Hospital return days for heart failure patientsUnplanned return visits | -17 · 922 cases | None | Jul 2022 – Jun 2025 |
| Hospital return days for pneumonia patientsUnplanned return visits | 18.6 · 860 cases | None | Jul 2022 – Jun 2025 |
| Pneumonia (PN) 30-Day Readmission RateUnplanned return visits | 18.7 · 827 cases | None | Jul 2023 – Jun 2025 |
| Rate of emergency department (ED) visits for patients receiving outpatient chemotherapyUnplanned return visits | 6.1 (4.5 to 8.2) · 313 cases | No different | Jan 2024 – Dec 2024 |
| Rate of inpatient admissions for patients receiving outpatient chemotherapyUnplanned return visits | 13.4 (10.6 to 16.5) · 313 cases | No different | Jan 2024 – Dec 2024 |
| Rate of readmission after hip/knee replacementUnplanned return visits | 6.1 · 144 cases | None | Jul 2023 – Jun 2025 |
| Rate of readmission for CABGUnplanned return visits | 10.3 · 80 cases | None | Jul 2023 – Jun 2025 |
| Rate of readmission for chronic obstructive pulmonary disease (COPD) patientsUnplanned return visits | 20.7 · 237 cases | None | Jul 2023 – Jun 2025 |
| Rate of unplanned hospital visits after colonoscopy (per 1,000 colonoscopies)Unplanned return visits | 12.8 (10 to 16.1) · 1,639 cases | No different | Jan 2022 – Dec 2024 |
| Ratio of unplanned hospital visits after hospital outpatient surgeryUnplanned return visits | 0.9 (0.8 to 1.1) · 1,619 cases | No different | Jan 2024 – Dec 2024 |
What patients said (1,535 patients answered, 22% of those asked)
| Cleanliness | 4 |
| Nurse communication | 4 |
| Doctor communication | 4 |
| Communication about medicines | 3 |
| Discharge information | 3 |
| Overall hospital rating | 4 |
| Quietness | 2 |
| Recommend hospital | 5 |
| Room was "always" clean | 75% |
| Nurses "always" communicated well | 79% |
| Doctors "always" communicated well | 81% |
| Staff "always" explained | 61% |
| Yes, staff "did" give patients this information | 86% |
| Yes, staff "did" give patients information about help after discharge | 86% |
| Doctors "always" explained things so they could understand | 76% |
| Doctors "always" listened carefully | 80% |
| Doctors "always" treated them with courtesy and respect | 87% |
| Patients who gave a rating of "9" or "10" (high) | 76% |
| Staff "always" explained new medications | 76% |
| Nurses "always" explained things so they could understand | 75% |
| Nurses "always" listened carefully | 76% |
| Nurses "always" treated them with courtesy and respect | 87% |
| "Always" quiet at night | 47% |
| "YES", patients would definitely recommend the hospital | 80% |
| Staff "always" explained possible side effects | 46% |
| Yes, staff "did" give patients information about possible symptoms | 86% |
Original Medicare doctor bills
$80,783
Medicare paid this office $80,783 for 331 people.
This is what Medicare paid the clinician — not Medicare Advantage, and not the pharmacy.
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 100 | $24,917 | $105 |
| Hospital discharge day management, more than 30 minutes | 176 | $19,563 | $102 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 131 | $16,936 | $69 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 106 | $16,152 | $151 |
| Initial hospital care with straightforward or low-level medical decision making at least 55 minutes | 13 | $1,400 | $108 |
See all 6 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 100 | $24,917 | $105 |
| Hospital discharge day management, more than 30 minutes | 176 | $19,563 | $102 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 131 | $16,936 | $69 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 106 | $16,152 | $151 |
| Initial hospital care with straightforward or low-level medical decision making at least 55 minutes | 13 | $1,400 | $108 |
| Subsequent hospital care with straightforward or low level of medical decision making, per day at least 25 minutes | 12 | $922 | $44 |
Who their Medicare patients are
331 Original Medicare patients in 2024. Average age 81 · Under 65 5% · 85 and older 39% · Women 54% · Also on Medicaid 23% · Health risk score 2.06. At or below the middle of the specialty; the typical hospitalist clinician is at 2.49.
Conditions among them: High blood pressure 75% · Chronic kidney disease 45% · Diabetes 40% · Coronary heart disease 40% · Heart failure 37% · Atrial fibrillation 35% · Depression 30% · Dementia 28% · Cancer 23% · Stroke 22% · COPD 20%.
The office billed $309,703, Medicare allowed $103,708 and paid $80,783; for 825 services of 12 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
| 2024 | 331 | 825 | 81 | 2.06 | $309,703 | $80,783 |
| 2023 | 358 | 990 | 81 | 1.90 | $378,129 | $103,728 |
| 2022 | 314 | 779 | 81 | 2.41 | $303,027 | $80,084 |
| 2021 | 319 | 775 | 81 | 2.04 | $302,028 | $82,575 |
| 2020 | 310 | 727 | 80 | 2.04 | $260,614 | $80,591 |
| 2019 | 337 | 906 | 80 | 2.20 | $299,425 | $89,708 |
| 2018 | 319 | 921 | 80 | 2.43 | $289,436 | $88,599 |
| 2017 | 305 | 807 | 80 | 2.44 | $253,542 | $78,218 |
| 2016 | 270 | 754 | 79 | 2.32 | $234,337 | $73,791 |
| 2015 | 300 | 790 | 80 | 2.36 | $249,832 | $82,915 |
| 2014 | 304 | 997 | 81 | 1.90 | $301,484 | $92,242 |
| 2013 | 267 | 765 | 80 | 2.18 | $242,244 | $70,677 |
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: 5 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 119 | $39,375 | $110 |
| Hospital discharge day management, more than 30 minutes | 182 | $20,785 | $105 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 128 | $20,549 | $159 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 150 | $19,346 | $73 |
| Initial hospital care with straightforward or low-level medical decision making at least 55 minutes | 18 | $2,062 | $115 |
2022: 6 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 120 | $31,522 | $94 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 101 | $18,333 | $178 |
| Hospital discharge day management, more than 30 minutes | 119 | $12,819 | $101 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 91 | $9,414 | $66 |
| Initial hospital observation care per day, typically 70 minutes | 23 | $3,990 | $166 |
| Hospital observation care on day of discharge | 22 | $1,405 | $64 |
2021: 7 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 115 | $27,354 | $95 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 122 | $22,554 | $183 |
| Hospital discharge day management, more than 30 minutes | 127 | $13,067 | $99 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 70 | $9,241 | $67 |
| Initial hospital observation care per day, typically 70 minutes | 24 | $3,765 | $157 |
| Hospital observation care on day of discharge | 26 | $1,767 | $65 |
| Initial hospital care with straightforward or low-level medical decision making at least 55 minutes | 11 | $1,379 | $125 |
2020: 7 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 97 | $25,013 | $98 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 120 | $23,843 | $186 |
| Hospital discharge day management, more than 30 minutes | 111 | $12,173 | $101 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 69 | $8,332 | $68 |
| Initial hospital observation care per day, typically 70 minutes | 31 | $4,938 | $159 |
| Hospital observation care on day of discharge | 30 | $2,103 | $70 |
| Initial hospital care with straightforward or low-level medical decision making at least 55 minutes | 12 | $1,536 | $128 |
2019: 6 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 125 | $26,865 | $94 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 119 | $22,275 | $183 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 123 | $15,708 | $65 |
| Hospital discharge day management, more than 30 minutes | 146 | $15,094 | $98 |
| Initial hospital observation care per day, typically 70 minutes | 22 | $3,342 | $152 |
| Hospital observation care on day of discharge | 25 | $1,695 | $68 |
2018: 7 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 112 | $27,694 | $93 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 105 | $19,310 | $179 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 135 | $17,650 | $65 |
| Hospital discharge day management, more than 30 minutes | 133 | $14,516 | $99 |
| Initial hospital observation care per day, typically 70 minutes | 25 | $4,040 | $162 |
| Hospital observation care on day of discharge | 21 | $1,471 | $67 |
| Subsequent hospital care with straightforward or low level of medical decision making, per day at least 25 minutes | 11 | $490 | $35 |
2017: 6 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 111 | $24,772 | $93 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 98 | $18,049 | $177 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 117 | $14,585 | $63 |
| Hospital discharge day management, more than 30 minutes | 127 | $13,271 | $98 |
| Initial hospital observation care per day, typically 70 minutes | 19 | $3,022 | $159 |
| Hospital observation care on day of discharge | 19 | $1,235 | $65 |
2016: 7 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 102 | $24,015 | $92 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 99 | $18,387 | $180 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 101 | $12,958 | $64 |
| Hospital discharge day management, more than 30 minutes | 100 | $10,250 | $97 |
| Initial hospital observation care per day, typically 70 minutes | 18 | $2,833 | $157 |
| Initial hospital care with straightforward or low-level medical decision making at least 55 minutes | 14 | $1,701 | $121 |
| Hospital observation care on day of discharge | 18 | $1,132 | $63 |
2015: 6 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 101 | $23,673 | $97 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 115 | $22,657 | $187 |
| Hospital discharge day management, more than 30 minutes | 130 | $14,305 | $102 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 101 | $13,264 | $67 |
| Initial hospital observation care per day, typically 70 minutes | 19 | $3,296 | $173 |
| Hospital observation care on day of discharge | 21 | $1,452 | $69 |
2014: 7 services
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 91 | $23,013 | $92 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 145 | $21,692 | $63 |
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 105 | $19,644 | $179 |
| Hospital discharge day management, more than 30 minutes | 134 | $13,854 | $96 |
| Initial hospital observation care per day, typically 70 minutes | 31 | $5,097 | $164 |
| Hospital observation care on day of discharge | 37 | $2,414 | $65 |
| Subsequent hospital care with straightforward or low level of medical decision making, per day at least 25 minutes | 16 | $868 | $35 |
2013: 9 services
| Initial hospital care with moderate level of medical decision making at least 75 minutes | 103 | $18,151 | $170 |
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 115 | $15,793 | $62 |
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 62 | $12,703 | $90 |
| Hospital discharge day management, more than 30 minutes | 99 | $9,768 | $94 |
| Initial hospital observation care per day, typically 70 minutes | 25 | $4,009 | $160 |
| Critical care, first 30-74 minutes | 11 | $2,109 | $192 |
| Hospital observation care on day of discharge | 30 | $1,917 | $64 |
| Subsequent hospital care with straightforward or low level of medical decision making, per day at least 25 minutes | 17 | $1,253 | $34 |
| Follow-up observation care per day, typically 25 minutes | 13 | $940 | $63 |
Medicaid work
$101 in 2023
Medicaid paid $101 for 12 billed services this clinician did in 2023, 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.
| Hospital inpatient or observation discharge day management; more than 30 minutes on the date of the encounter | 12 | $101 |
| 2023 | 12 | 1 | 12 | $101 |
Drugs they prescribed that Part D paid
$17,456
Pharmacies billed $17,456 in 2024.
This is pharmacy cost, not the office bill, and not what patients paid.
Opioids were 7% of their Part D prescriptions (17 of 250) in 2024. Above the middle of the specialty; the typical hospitalist clinician is at 4%.
216 generic and 34 brand-name prescriptions · $17,456 in drug cost · 46 antibiotic prescriptions to 40 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.
| Eliquis | 12 | $6,967 | $581 |
| Amoxicillin-Clavulanate Potass | 14 | $146 | $10 |
| Metoprolol | 15 | $138 | $9 |
| Pantoprazole | 11 | $94 | $9 |
| Furosemide | 19 | $91 | $5 |
See all 6 drugs
| Eliquis | 12 | $6,967 | $581 |
| Amoxicillin-Clavulanate Potass | 14 | $146 | $10 |
| Metoprolol | 15 | $138 | $9 |
| Pantoprazole | 11 | $94 | $9 |
| Furosemide | 19 | $91 | $5 |
| Cephalexin | 11 | $48 | $4 |
Year by year
| 2024 | 250 | 124 | 7% (17) | 14% | $17,456 |
| 2023 | 237 | 122 | 6% (13) | None | $15,564 |
| 2022 | 163 | 97 | None | 10% | $13,119 |
| 2021 | 231 | 104 | 5% (12) | None | $15,597 |
| 2020 | 190 | 105 | 8% (15) | 17% | $11,263 |
| 2019 | 158 | 87 | 9% (14) | None | $8,730 |
| 2018 | 234 | 98 | 5% (11) | 18% | $11,526 |
| 2017 | 175 | 87 | 6% (11) | None | $7,729 |
| 2016 | 144 | 76 | 10% (15) | 13% | $12,142 |
| 2015 | 219 | 94 | 8% (17) | 18% | $8,250 |
| 2014 | 221 | 97 | 10% (21) | None | $9,062 |
| 2013 | 161 | 70 | 11% (17) | None | $5,523 |
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
| Pantoprazole | 12 | $182 | $15 |
| Amoxicillin-Clavulanate Potass | 12 | $155 | $13 |
| Clopidogrel | 17 | $144 | $8 |
| Furosemide | 11 | $25 | $2 |
2022: 2 drugs
| Eliquis | 11 | $6,901 | $627 |
| Pantoprazole | 11 | $162 | $15 |
2021: 4 drugs
| Eliquis | 14 | $7,045 | $503 |
| Pantoprazole | 11 | $144 | $13 |
| Prednisone | 11 | $62 | $6 |
| Furosemide | 15 | $57 | $4 |
2020: 3 drugs
| Cephalexin | 13 | $81 | $6 |
| Furosemide | 11 | $49 | $4 |
| Prednisone | 11 | $46 | $4 |
2018: 1 drug
| Atorvastatin | 17 | $227 | $13 |
2017: 3 drugs
| Metoprolol | 11 | $246 | $22 |
| Atorvastatin | 11 | $182 | $17 |
| Furosemide | 16 | $40 | $3 |
2015: 2 drugs
| Venlafaxine Hcl Er | 11 | $834 | $76 |
| Prednisone | 19 | $94 | $5 |
2014: 3 drugs
| Amox Tr-Potassium Clavulanate | 11 | $97 | $9 |
| Hydrocodone-Acetaminophen | 11 | $79 | $7 |
| Furosemide | 11 | $39 | $4 |
Money from drug and device companies
$24 in 2025
| 2025 | 1 | 1 | None | $24 |
| 2020 | 1 | 1 | None | $26 |
Paid work is consulting, speaking, honoraria and royalties, as opposed to meals and travel.
A payment is not proof that care is biased.
| Heron Therapeutics | Aponvie | $24 | 1 payment
|
See the published payment
| Heron Therapeutics | Meals · 2025-10-16 | Aponvie | $24 |
See earlier years (2020)
2020: $26
| Boston Scientific | Rotablator | $26 | 1 payment
|
Professional record
- NPI
- 1639185143
- Licence
- CA A70755California A70755: Current · expires 2028-01-31
- Trained
- University of Michigan Medical School, 1998
- Gender
- Male
More record details
- Sole proprietor
- No
- Taxonomy
- Hospitalist (208M00000X); Internal medicine (207R00000X)
- Mailing address
- 325 Distel Cir, Los Altos, CA, 94022
- NPI first listed
- 2006-08-01
- NPI last updated
- 2021-02-22
- NPI record certified
- 2021-02-22
This is when the NPI record was last certified, not a medical board exam.