William F Johnston, MD
Emergency Medicine · San Mateo
- 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 · Cep America - California · 1,278 clinicians in this group
Looking this up.
Hospitals listed: San Mateo Medical Center. 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. Johnston’s office at (650) 573-2222 to ask if they take your plan before you enroll.
California Medical Board record
Licence A138944 · Current
Licensed to practise in California · since 2015 · expires 2027-03-31 · David Geffen School of Medicine at UCLA.
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.
- San Mateo Medical CenterSan Mateo, CAAcute Care Hospital · Government - Local · Has an emergency departmentPart of San Mateo County HealthPatients rate it 3 of 5 · 68% would definitely recommend itNo overall ratingNo measure marked better or worse than the national rate
See every measure and the patient survey for San Mateo Medical Center
Behind the star rating — Deaths: 0 better, 2 the same, 0 worse of 2 measures. Safety: 0 better, 2 the same, 0 worse of 2 measures. Readmissions: 0 better, 3 the same, 0 worse of 3 measures. The star rating is worked out from an earlier period than the measures below, so the two can disagree.
| Abdominopelvic accidental puncture or laceration rateComplications and deaths | 1.34 (0.25 to 2.43) · 45 cases | No different | Jul 2022 – Jun 2024 |
| CMS Medicare PSI 90: Patient safety and adverse events compositeComplications and deaths | 0.97 (0.48 to 1.47) | No different | Jul 2022 – Jun 2024 |
| Death rate for pneumonia patientsComplications and deaths | 13.9 · 25 cases | None | Jul 2022 – Jun 2025 |
| Hybrid Hospital-Wide All-Cause Risk Standardized Mortality RateComplications and deaths | 3.6 · 258 cases | None | Jul 2024 – Jun 2025 |
| Iatrogenic pneumothorax rateComplications and deaths | 0.21 (0 to 0.44) · 379 cases | No different | Jul 2022 – Jun 2024 |
| In-hospital fall-associated fracture rateComplications and deaths | 0.26 (0.05 to 0.48) · 381 cases | No different | Jul 2022 – Jun 2024 |
| Perioperative pulmonary embolism or deep vein thrombosis rateComplications and deaths | 3.44 (0.82 to 6.05) · 57 cases | No different | Jul 2022 – Jun 2024 |
| Postoperative hemorrhage or hematoma rateComplications and deaths | 2.64 (0.92 to 4.37) · 57 cases | No different | Jul 2022 – Jun 2024 |
| Pressure ulcer rateComplications and deaths | 0.53 (0 to 1.76) · 296 cases | No different | Jul 2022 – Jun 2024 |
| Clostridium Difficile (C.Diff)Infections | 0.661 | No different | Oct 2024 – Sep 2025 |
| Heart failure (HF) 30-Day Readmission RateUnplanned return visits | 21.8 · 47 cases | None | Jul 2023 – Jun 2025 |
| Hospital return days for pneumonia patientsUnplanned return visits | -2.3 · 25 cases | None | Jul 2022 – Jun 2025 |
| Pneumonia (PN) 30-Day Readmission RateUnplanned return visits | 16.6 · 76 cases | None | Jul 2023 – Jun 2025 |
| Rate of unplanned hospital visits after colonoscopy (per 1,000 colonoscopies)Unplanned return visits | 14 (10.4 to 18.9) · 167 cases | No different | Jan 2022 – Dec 2024 |
What patients said (208 patients answered, 15% of those asked)
| Cleanliness | 4 |
| Nurse communication | 3 |
| Doctor communication | 3 |
| Communication about medicines | 3 |
| Discharge information | 4 |
| Overall hospital rating | 3 |
| Quietness | 2 |
| Recommend hospital | 3 |
| Room was "always" clean | 78% |
| Nurses "always" communicated well | 76% |
| Doctors "always" communicated well | 79% |
| Staff "always" explained | 62% |
| Yes, staff "did" give patients this information | 87% |
| Yes, staff "did" give patients information about help after discharge | 88% |
| Doctors "always" explained things so they could understand | 74% |
| Doctors "always" listened carefully | 77% |
| Doctors "always" treated them with courtesy and respect | 84% |
| Patients who gave a rating of "9" or "10" (high) | 70% |
| Staff "always" explained new medications | 72% |
| Nurses "always" explained things so they could understand | 72% |
| Nurses "always" listened carefully | 73% |
| Nurses "always" treated them with courtesy and respect | 82% |
| "Always" quiet at night | 47% |
| "YES", patients would definitely recommend the hospital | 68% |
| Staff "always" explained possible side effects | 51% |
| Yes, staff "did" give patients information about possible symptoms | 86% |
Original Medicare doctor bills
$5,272
Medicare paid this office $5,272 for 43 people.
This is what Medicare paid the clinician — not Medicare Advantage, and not the pharmacy.
| Emergency department visit with moderate level of medical decision making | 22 | $2,279 | $99 |
| Emergency department visit with high level of medical decision making | 12 | $1,873 | $156 |
Who their Medicare patients are
43 Original Medicare patients in 2024. Average age 68 · Women 56% · Health risk score 1.18. At or below the middle of the specialty; the typical emergency medicine clinician is at 2.01.
Conditions among them: High blood pressure 74% · Diabetes 35% · Depression 28%.
The office billed $42,976, Medicare allowed $6,791 and paid $5,272; for 56 services of 13 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 | 43 | 56 | 68 | 1.18 | $42,976 | $5,272 |
| 2023 | 35 | 47 | 69 | 1.31 | $37,913 | $4,376 |
| 2022 | 47 | 59 | 68 | 1.26 | $44,654 | $5,830 |
| 2021 | 58 | 87 | 69 | 2.20 | $56,953 | $7,672 |
| 2020 | 158 | 258 | 70 | 2.27 | $150,425 | $22,537 |
| 2019 | 294 | 509 | 71 | 2.64 | $255,278 | $39,100 |
| 2018 | 231 | 407 | 71 | 2.73 | $155,142 | $34,892 |
| 2017 | 27 | 28 | 68 | 1.64 | $10,357 | $1,844 |
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
| Emergency department visit with high level of medical decision making | 13 | $1,536 | $118 |
| Emergency department visit with moderate level of medical decision making | 15 | $1,474 | $98 |
2022: 3 services
| Emergency department visit with high level of medical decision making | 14 | $2,407 | $160 |
| Emergency department visit with moderate level of medical decision making | 12 | $1,070 | $89 |
| Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only | 11 | $73 | $7 |
2021: 4 services
| Emergency department visit with high level of medical decision making | 23 | $3,426 | $149 |
| Critical care, first 30-74 minutes | 13 | $2,770 | $213 |
| Emergency department visit with moderate level of medical decision making | 12 | $814 | $68 |
| Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only | 29 | $219 | $8 |
2020: 5 services
| Emergency department visit with high level of medical decision making | 59 | $9,050 | $148 |
| Critical care, first 30-74 minutes | 34 | $6,913 | $203 |
| Emergency department visit with moderate level of medical decision making | 32 | $3,409 | $103 |
| Emergency department visit with low level of medical decision making | 16 | $910 | $57 |
| Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only | 92 | $738 | $8 |
2019: 5 services
| Emergency department visit with high level of medical decision making | 168 | $24,923 | $145 |
| Critical care, first 30-74 minutes | 26 | $5,027 | $193 |
| Emergency department visit with moderate level of medical decision making | 43 | $4,172 | $95 |
| Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only | 197 | $1,589 | $7 |
| Emergency department visit with low level of medical decision making | 20 | $1,007 | $50 |
2018: 4 services
| Emergency department visit with high level of medical decision making | 145 | $25,463 | $164 |
| Emergency department visit with moderate level of medical decision making | 34 | $4,011 | $111 |
| Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only | 160 | $1,491 | $9 |
| Emergency department visit with low level of medical decision making | 12 | $719 | $60 |
2017: 1 service
| Emergency department visit with moderate level of medical decision making | 20 | $1,788 | $85 |
Medicaid work
$84,907 in 2024
Medicaid paid $84,907 for 1,282 billed services this clinician did in 2024, up to 81 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.
| EMERGENCY DEPT VISIT MOD MDM | 575 | $43,498 |
| EMERGENCY DEPARTMENT VISIT HIGH MDM | 265 | $31,517 |
| Service | 208 | $7,704 |
| Service | 128 | $1,014 |
| COMPREHENSIVE METABOLIC PANEL | 40 | $429 |
| Electrocardiogram, routine ECG with at least 12 leads; interpretation and report only | 25 | $425 |
| Blood count; complete (CBC), automated (Hgb, Hct, RBC, WBC and platelet count) and automated differential WBC count | 41 | $320 |
| 2024 | 1,282 | 7 | 81 | $84,907 |
| 2023 | 2,561 | 14 | 88 | $124,791 |
| 2022 | 1,564 | 13 | 56 | $72,869 |
| 2021 | 598 | 9 | 39 | $25,154 |
| 2020 | 413 | 4 | 32 | $14,492 |
| 2019 | 1,221 | 7 | 43 | $44,821 |
| 2018 | 1,263 | 9 | 49 | $40,200 |
See the largest Medicaid services in earlier years
2023
| EMERGENCY DEPT VISIT MOD MDM | 854 | $61,282 |
| EMERGENCY DEPARTMENT VISIT HIGH MDM | 294 | $31,993 |
| Service | 462 | $17,251 |
| Infectious agent detection by nucleic acid (DNA or RNA); severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (coronavirus disease [COVID-19]) and influenza virus types A and B, multiplex amplified probe technique | 24 | $3,423 |
| Service | 360 | $2,807 |
| Electrocardiogram, routine ECG with at least 12 leads; interpretation and report only | 151 | $2,210 |
| COMPREHENSIVE METABOLIC PANEL | 120 | $1,759 |
| Blood count; complete (CBC), automated (Hgb, Hct, RBC, WBC and platelet count) and automated differential WBC count | 135 | $1,490 |
| EMERGENCY DEPT VISIT LOW MDM | 27 | $1,431 |
| Electrocardiogram, routine ECG with at least 12 leads; tracing only, without interpretation and report | 27 | $489 |
| Injection, ketorolac tromethamine, per 15 mg | 48 | $267 |
| URINE PREGNANCY TEST | 13 | $150 |
2022
| EMERGENCY DEPT VISIT LOW MDM | 433 | $26,823 |
| EMERGENCY DEPT VISIT MOD MDM | 273 | $17,779 |
| EMERGENCY DEPARTMENT VISIT HIGH MDM | 147 | $10,847 |
| Service | 242 | $9,027 |
| Infectious agent detection by nucleic acid (DNA or RNA); severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (coronavirus disease [COVID-19]) and influenza virus types A and B, multiplex amplified probe technique | 30 | $4,279 |
| Service | 144 | $1,063 |
| COMPREHENSIVE METABOLIC PANEL | 81 | $1,024 |
| Blood count; complete (CBC), automated (Hgb, Hct, RBC, WBC and platelet count) and automated differential WBC count | 87 | $812 |
| Electrocardiogram, routine ECG with at least 12 leads; tracing only, without interpretation and report | 25 | $482 |
| URINE PREGNANCY TEST | 25 | $289 |
| Electrocardiogram, routine ECG with at least 12 leads; interpretation and report only | 14 | $189 |
| Injection, ketorolac tromethamine, per 15 mg | 28 | $165 |
2021
| EMERGENCY DEPT VISIT LOW MDM | 163 | $7,596 |
| EMERGENCY DEPARTMENT VISIT HIGH MDM | 93 | $6,981 |
| EMERGENCY DEPT VISIT MOD MDM | 134 | $6,817 |
| Service | 74 | $2,639 |
| Electrocardiogram, routine ECG with at least 12 leads; interpretation and report only | 55 | $502 |
| Service | 36 | $280 |
| COMPREHENSIVE METABOLIC PANEL | 15 | $180 |
| Blood count; complete (CBC), automated (Hgb, Hct, RBC, WBC and platelet count) and automated differential WBC count | 14 | $123 |
| Urinalysis, by dip stick or tablet reagent for bilirubin, glucose, hemoglobin, ketones, leukocytes, nitrite, pH, protein, specific gravity, urobilinogen, any number of these constituents; automated, without microscopy | 14 | $36 |
2020
| EMERGENCY DEPT VISIT MOD MDM | 111 | $5,656 |
| EMERGENCY DEPARTMENT VISIT HIGH MDM | 56 | $3,960 |
| EMERGENCY DEPT VISIT LOW MDM | 142 | $3,839 |
| Electrocardiogram, routine ECG with at least 12 leads; interpretation and report only | 104 | $1,037 |
2019
| EMERGENCY DEPARTMENT VISIT HIGH MDM | 216 | $15,505 |
| EMERGENCY DEPT VISIT MOD MDM | 315 | $14,244 |
| EMERGENCY DEPT VISIT LOW MDM | 334 | $9,131 |
| Service | 92 | $3,460 |
| Electrocardiogram, routine ECG with at least 12 leads; interpretation and report only | 236 | $2,332 |
| COMPREHENSIVE METABOLIC PANEL | 13 | $80 |
| Blood count; complete (CBC), automated (Hgb, Hct, RBC, WBC and platelet count) and automated differential WBC count | 15 | $70 |
2018
| EMERGENCY DEPARTMENT VISIT HIGH MDM | 225 | $15,667 |
| EMERGENCY DEPT VISIT MOD MDM | 247 | $9,848 |
| EMERGENCY DEPT VISIT LOW MDM | 302 | $8,348 |
| Service | 81 | $3,041 |
| Electrocardiogram, routine ECG with at least 12 leads; interpretation and report only | 242 | $2,375 |
| COMPREHENSIVE METABOLIC PANEL | 55 | $390 |
| Blood count; complete (CBC), automated (Hgb, Hct, RBC, WBC and platelet count) and automated differential WBC count | 84 | $386 |
| Electrocardiogram, routine ECG with at least 12 leads; tracing only, without interpretation and report | 13 | $113 |
| Urinalysis, by dip stick or tablet reagent for bilirubin, glucose, hemoglobin, ketones, leukocytes, nitrite, pH, protein, specific gravity, urobilinogen, any number of these constituents; automated, with microscopy | 14 | $33 |
Money from drug and device companies
$43 in 2025
A payment is not proof that care is biased.
| Applied Medical Resources | None | $43 | 1 payment
|
See the published payment
| Applied Medical Resources | Meals · 2025-09-27 | None | $43 |
Checkups this office reported
Medicare did not publish checkup rates for this clinician.
- Medicare’s overall office score
- 94.6 / 100
- Scores the office’s reporting and systems. It is not a grade for how the doctor treats you.
Professional record
- NPI
- 1417366584
- Licence
- CA A138944California A138944: Current · expires 2027-03-31
- Gender
- Male
More record details
- Sole proprietor
- No
- Taxonomy
- Federal specialty code 207P00000X (207P00000X)
- Mailing address
- 2015 Ray Dr, Burlingame, CA, 94010
- NPI first listed
- 2014-08-03
- NPI last updated
- 2021-08-12
- NPI record certified
- 2021-08-12
This is when the NPI record was last certified, not a medical board exam.
Extra NPI addresses: 30 Prospect Ave, Hackensack, NJ, 07601 · 222 W 39th Ave, San Mateo, CA, 94403 · 1200 El Camino Real, South San Francisco, CA, 94080