Hospitals listed: San Mateo Medical Center. That is not proof they admit you there this week.
Plans that list them
2 plans · 2 carriers
A missing listing does not mean out of network. Directories change, and a listing does not cover every office. Call Dr. Shields’s office at (650) 573-2222 to confirm they take your plan. Ask about the office you use, its medical group, referrals and appointments.
2 of 2 plans
Plans whose provider directory lists this clinician
Licensed to practise in California · since 1980 · expires 2028-03-31 · University of California San Francisco School of Medicine.
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 it
No 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.
Every scored measure at San Mateo Medical Center
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
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)
Patient survey stars by topic at San Mateo Medical Center
Cleanliness
4
Nurse communication
3
Doctor communication
3
Communication about medicines
3
Discharge information
4
Overall hospital rating
3
Quietness
2
Recommend hospital
3
Share of patients giving the best answer at San Mateo Medical Center
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
$9,304
Medicare paid this office $9,304 for 52 people.
This is what Medicare paid the clinician — not Medicare Advantage, and not the pharmacy.
Largest Original Medicare bills
Removal of polyps or growths of large bowel using an endoscope with mechanical snare
11
$2,306
$210
Procedures Medicare counted
Procedure volume Medicare published
Colonoscopy
33
More than 55% of doctors who do this
Upper gastrointestinal (GI) endoscopy for acid reflux
26
More than 54% of doctors who do this
Who their Medicare patients are
52 Original Medicare patients in 2024. Average age 68 · 85 and older 0% · Women 40% · Health risk score 1.29. At or below the middle of the specialty; the typical gastroenterology clinician is at 1.42.
Conditions among them: High blood pressure 75% · Diabetes 37%.
The office billed $42,644, Medicare allowed $11,660 and paid $9,304; for 60 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
Original Medicare by year
2024
52
60
68
1.29
$42,644
$9,304
2023
67
80
70
1.11
$62,282
$10,107
2022
61
79
69
0.92
$65,030
$10,339
2021
210
344
73
0.95
$274,080
$46,555
2020
186
449
74
0.90
$242,739
$45,600
2019
263
644
75
0.85
$356,090
$67,775
2018
262
727
75
0.98
$343,681
$62,661
2017
262
712
75
0.93
$318,797
$63,179
2016
296
545
74
0.94
$376,226
$74,988
2015
297
556
75
0.93
$288,065
$83,477
2014
274
571
75
0.87
$240,321
$83,330
2013
319
645
75
0.95
$264,149
$97,630
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: 3 services
Original Medicare services billed in 2023
Removal of polyps or growths of large bowel using an endoscope with mechanical snare
14
$2,898
$207
Diagnostic exam of large bowel using a flexible endoscope
15
$1,498
$100
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope
15
$1,185
$79
2022: 2 services
Original Medicare services billed in 2022
Diagnostic exam of large bowel using a flexible endoscope
27
$2,984
$111
Removal of polyps or growths of large bowel using an endoscope with mechanical snare
12
$2,186
$182
2021: 9 services
Original Medicare services billed in 2021
Removal of polyps or growths of large bowel using an endoscope with mechanical snare
53
$10,709
$202
Colorectal cancer screening; colonoscopy on individual at high risk
35
$7,493
$214
Short return visit (20+ min)
41
$5,440
$82
Diagnostic exam of large bowel using a flexible endoscope
25
$4,061
$162
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope
38
$3,728
$96
Biopsy of large bowel using a flexible endoscope
31
$2,862
$92
Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk
13
$2,780
$214
Diagnostic exam of esophagus, stomach, and/or upper small bowel using a flexible endoscope
14
$1,021
$73
Moderate sedation services provided by the same physician or other qualified health care professional performing a gastrointestinal endoscopic service that sedation supports, requiring the presence of an independent trained observer to assist in the monito
18
$72
$4
2020: 8 services
Original Medicare services billed in 2020
Short return visit (20+ min)
65
$8,541
$68
Removal of polyps or growths of large bowel using an endoscope with mechanical snare
33
$6,341
$186
Colorectal cancer screening; colonoscopy on individual at high risk
21
$4,538
$216
Biopsy of large bowel using a flexible endoscope
35
$4,463
$128
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope
38
$3,764
$97
New patient visit (60+ min)
16
$2,777
$174
Diagnostic exam of large bowel using a flexible endoscope
16
$2,410
$151
Moderate sedation services provided by the same physician or other qualified health care professional performing a gastrointestinal endoscopic service that sedation supports, requiring the presence of an independent trained observer to assist in the monito
87
$424
$5
2019: 11 services
Original Medicare services billed in 2019
Removal of polyps or growths of large bowel using an endoscope with mechanical snare
45
$9,137
$203
Biopsy of large bowel using a flexible endoscope
63
$9,082
$144
Short return visit (20+ min)
61
$6,468
$61
Colorectal cancer screening; colonoscopy on individual at high risk
29
$6,166
$213
New patient visit (60+ min)
35
$6,017
$172
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope
56
$5,047
$90
Diagnostic exam of large bowel using a flexible endoscope
27
$3,819
$141
Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk
16
$3,406
$213
New patient visit (45+ min)
18
$2,618
$145
Return visit (30+ min)
14
$1,654
$103
Moderate sedation services provided by the same physician or other qualified health care professional performing a gastrointestinal endoscopic service that sedation supports, requiring the presence of an independent trained observer to assist in the monito
161
$736
$5
2018: 11 services
Original Medicare services billed in 2018
Removal of polyps or growths of large bowel using an endoscope with mechanical snare
44
$8,600
$187
Colorectal cancer screening; colonoscopy on individual at high risk
32
$6,801
$213
Short return visit (20+ min)
55
$6,319
$64
New patient visit (60+ min)
36
$5,950
$165
Biopsy of large bowel using a flexible endoscope
40
$5,896
$147
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope
47
$4,373
$93
Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk
20
$4,247
$212
Diagnostic exam of large bowel using a flexible endoscope
28
$4,081
$146
Use of a drug to induce depression of consciousness by physician performing a procedure, each additional 15 minutes
126
$1,412
$11
Return visit (30+ min)
11
$994
$90
Moderate sedation services provided by the same physician or other qualified health care professional performing a gastrointestinal endoscopic service that sedation supports, requiring the presence of an independent trained observer to assist in the monito
152
$715
$5
2017: 12 services
Original Medicare services billed in 2017
Colorectal cancer screening; colonoscopy on individual at high risk
38
$8,042
$212
Removal of polyps or growths of large bowel using an endoscope with mechanical snare
37
$6,948
$188
Short return visit (20+ min)
60
$6,160
$60
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope
54
$5,491
$100
New patient visit (60+ min)
28
$5,293
$189
Biopsy of large bowel using a flexible endoscope
34
$5,147
$151
Diagnostic exam of large bowel using a flexible endoscope
22
$3,360
$153
Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk
14
$2,955
$211
New patient visit (45+ min)
22
$2,770
$126
Return visit (30+ min)
15
$1,722
$101
Use of a drug to induce depression of consciousness by physician performing a procedure, each additional 15 minutes
108
$1,278
$11
Moderate sedation services provided by the same physician or other qualified health care professional performing a gastrointestinal endoscopic service that sedation supports, requiring the presence of an independent trained observer to assist in the monito
139
$677
$5
2016: 11 services
Original Medicare services billed in 2016
Short return visit (20+ min)
78
$9,201
$62
Colorectal cancer screening; colonoscopy on individual at high risk
42
$9,126
$217
Removal of polyps or growths of large bowel using an endoscope with mechanical snare
45
$8,369
$186
New patient visit (60+ min)
42
$7,401
$176
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope
61
$6,504
$107
Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk
27
$5,873
$218
Diagnostic exam of large bowel using a flexible endoscope
22
$3,521
$160
Biopsy of large bowel using a flexible endoscope
19
$3,221
$170
New patient visit (45+ min)
20
$2,780
$139
Removal of polyps or growths of large bowel using a flexible endoscope with electrical cautery
16
$1,481
$93
Diagnostic exam of anus using an endoscope
12
$1,067
$89
2015: 13 services
Original Medicare services billed in 2015
Colorectal cancer screening; colonoscopy on individual at high risk
49
$11,350
$232
Short return visit (20+ min)
87
$9,557
$62
New patient visit (60+ min)
51
$9,099
$178
Removal of polyps or growths of large bowel using an endoscope with mechanical snare
32
$7,896
$247
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope
72
$7,574
$105
Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk
28
$6,471
$231
Diagnostic exam of large bowel using a flexible endoscope
34
$6,087
$179
Removal of external hemorrhoids by rubber banding
11
$5,996
$261
Biopsy of large bowel using a flexible endoscope
20
$4,380
$219
Removal of polyps or growths of large bowel using a flexible endoscope with electrical cautery
14
$2,271
$162
New patient visit (45+ min)
11
$1,663
$151
Diagnostic exam of anus using an endoscope
11
$1,025
$85
Return visit (30+ min)
11
$997
$91
2014: 13 services
Original Medicare services billed in 2014
Short return visit (20+ min)
91
$11,129
$65
Colorectal cancer screening; colonoscopy on individual at high risk
45
$10,839
$241
Removal of external hemorrhoids by rubber banding
13
$9,103
$253
New patient visit (60+ min)
50
$8,682
$174
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope
54
$5,901
$107
Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk
23
$5,540
$241
Biopsy of large bowel using a flexible endoscope
20
$4,444
$212
Diagnostic exam of large bowel using a flexible endoscope
22
$4,198
$183
Removal of polyps or growths in large bowel using an endoscope
13
$3,716
$286
Removal of polyps or growths of large bowel using an endoscope with mechanical snare
14
$3,394
$242
Removal of polyps or growths of large bowel using a flexible endoscope with electrical cautery
21
$2,815
$134
Diagnostic exam of anus using an endoscope
25
$2,398
$86
Return visit (30+ min)
21
$2,011
$91
2013: 14 services
Original Medicare services billed in 2013
Short return visit (20+ min)
100
$12,235
$63
Diagnostic exam of large bowel using a flexible endoscope
60
$11,042
$184
Removal of external hemorrhoids by rubber banding
16
$10,687
$254
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope
63
$7,844
$119
Colorectal cancer screening; colonoscopy on individual at high risk
32
$7,741
$242
New patient visit (60+ min)
38
$6,981
$184
Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk
28
$6,780
$242
Removal of polyps or growths of large bowel using an endoscope with mechanical snare
24
$5,318
$222
Removal of polyps or growths of large bowel using a flexible endoscope with electrical cautery
24
$3,915
$163
Biopsy of large bowel using a flexible endoscope
19
$3,460
$182
Removal of polyps or growths in large bowel using an endoscope
11
$2,977
$271
Return visit (30+ min)
27
$2,690
$100
New patient visit (45+ min)
16
$2,139
$134
Diagnostic exam of anus using an endoscope
18
$1,601
$84
Medicaid work
$37,820 in 2024
Medicaid paid $37,820 for 134 billed services this clinician did in 2024, up to 25 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
DIAGNOSTIC COLONOSCOPY
94
$30,109
Upper gastrointestinal endoscopy with biopsy
28
$5,711
Diagnostic upper gastrointestinal endoscopy
12
$2,000
Medicaid work by year
2024
134
3
25
$37,820
2023
296
4
30
$91,881
2022
58
1
19
$16,804
See the largest Medicaid services in earlier years
2023
Largest Medicaid services in 2023
DIAGNOSTIC COLONOSCOPY
164
$51,934
COLONOSCOPY W/LESION REMOVAL
76
$28,287
Upper gastrointestinal endoscopy with biopsy
42
$8,600
Diagnostic upper gastrointestinal endoscopy
14
$3,059
2022
Largest Medicaid services in 2022
DIAGNOSTIC COLONOSCOPY
58
$16,804
Drugs they prescribed that Part D paid
$8,245
Pharmacies billed $8,245 in 2024.
This is pharmacy cost, not the office bill, and not what patients paid.
Opioids were 0% of their Part D prescriptions (0 of 31) in 2024. Too few prescriptions to compare fairly with other clinicians.
23 generic and fewer than 11 brand-name prescriptions · $8,245 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
Entecavir
11
$2,128
$193
Year by year
Part D prescribing by year
2024
31
11
0% (0)
—None
$8,245
2023
38
12
0% (0)
39%
$24,952
2022
87
30
0% (0)
—None
$29,334
2021
309
147
—None
43%
$172,972
2020
309
129
0% (0)
41%
$189,446
2019
341
170
0% (0)
50%
$186,809
2018
423
167
0% (0)
43%
$202,324
2017
471
163
0% (0)
33%
$185,636
2016
582
186
0% (0)
39%
$209,674
2015
590
198
0% (0)
—None
$135,962
2014
535
169
—None
—None
$122,150
2013
509
162
—None
48%
$155,652
Part D prescriptions only. A drug prescribed to fewer than 11 people in a year is hidden.
See the drugs prescribed each year
2023: 1 drug
Part D drugs prescribed in 2023
Entecavir
12
$867
$72
2022: 1 drug
Part D drugs prescribed in 2022
Omeprazole
16
$410
$26
2021: 7 drugs
Part D drugs prescribed in 2021
Humira
11
$71,594
$6,509
Humira
12
$69,312
$5,776
Suprep
100
$11,098
$111
Mesalamine
13
$7,146
$550
Omeprazole
45
$1,269
$28
Famotidine
11
$317
$29
Lansoprazole
12
$76
$6
2020: 5 drugs
Part D drugs prescribed in 2020
Humira
15
$80,771
$5,385
Mesalamine
13
$8,791
$676
Linzess
17
$7,709
$453
Suprep
64
$6,723
$105
Omeprazole
40
$847
$21
2019: 5 drugs
Part D drugs prescribed in 2019
Suprep
109
$10,804
$99
Linzess
16
$6,941
$434
Omeprazole
42
$1,592
$38
Sulfasalazine
13
$609
$47
Ciprofloxacin
12
$164
$14
2018: 13 drugs
Part D drugs prescribed in 2018
Humira
17
$80,257
$4,721
Xifaxan
12
$25,363
$2,114
Mesalamine
20
$7,587
$379
Linzess
19
$7,341
$386
Suprep
75
$7,033
$94
Mercaptopurine
24
$2,004
$84
Cholestyramine
15
$1,939
$129
Omeprazole
60
$1,731
$29
Sulfasalazine
16
$691
$43
Peg 3350-Electrolyte
27
$367
$14
Gavilyte-N
11
$179
$16
Pantoprazole
17
$114
$7
Amitriptyline
13
$108
$8
2017: 14 drugs
Part D drugs prescribed in 2017
Xifaxan
14
$26,510
$1,894
Lialda
12
$12,814
$1,068
Linzess
21
$8,164
$389
Cholestyramine
23
$3,333
$145
Mercaptopurine
23
$2,285
$99
Omeprazole
61
$1,668
$27
Rabeprazole
17
$1,546
$91
Peg 3350-Electrolyte
71
$981
$14
Sulfasalazine
11
$706
$64
Gavilyte-N
32
$564
$18
Esomeprazole Magnesium
12
$539
$45
Pantoprazole
14
$207
$15
Atorvastatin
17
$198
$12
Diltiazem 24hr Er
11
$123
$11
2016: 19 drugs
Part D drugs prescribed in 2016
Humira
20
$112,002
$5,600
Lialda
37
$26,952
$728
Xifaxan
11
$20,453
$1,859
Creon
17
$9,459
$556
Ursodiol
16
$2,863
$179
Apriso
11
$2,258
$205
Mercaptopurine
22
$2,219
$101
Omeprazole
96
$2,217
$23
Cholestyramine
12
$2,180
$182
Esomeprazole Magnesium
11
$1,745
$159
Rabeprazole
21
$1,325
$63
Peg 3350-Electrolyte
75
$1,160
$15
Sulfasalazine Dr
14
$915
$65
Gavilyte-N
32
$548
$17
Ranitidine
11
$327
$30
Pantoprazole
13
$211
$16
Diltiazem 24hr Er
13
$192
$15
Atorvastatin
20
$149
$7
Spironolactone
11
$136
$12
2015: 18 drugs
Part D drugs prescribed in 2015
Humira
15
$48,808
$3,254
Creon
19
$17,454
$919
Lialda
21
$13,518
$644
Apriso
17
$4,744
$279
Mercaptopurine
14
$1,928
$138
Rabeprazole
24
$1,667
$69
Celecoxib
11
$1,629
$148
Peg 3350-Electrolyte
89
$1,518
$17
Cholestyramine
12
$1,372
$114
Omeprazole
82
$1,356
$17
Sulfasalazine Dr
18
$1,344
$75
Transderm-Scop
11
$937
$85
Gavilyte-N
42
$787
$19
Zolpidem
11
$351
$32
Clotrimazole-Betamethasone
11
$306
$28
Diltiazem Er
12
$250
$21
Pantoprazole
14
$213
$15
Atorvastatin
15
$145
$10
2014: 15 drugs
Part D drugs prescribed in 2014
Humira
15
$39,856
$2,657
Lialda
18
$10,692
$594
Nexium
13
$4,608
$354
Apriso
16
$3,748
$234
Rabeprazole
27
$2,276
$84
Omeprazole
82
$1,759
$21
Peg-3350
76
$1,356
$18
Sulfazine Ec
16
$976
$61
Mercaptopurine
18
$897
$50
Gavilyte-N
25
$435
$17
Clotrimazole-Betamethasone
12
$336
$28
Atorvastatin
22
$305
$14
Diltiazem Er
13
$300
$23
Famotidine
15
$201
$13
Zolpidem
16
$104
$7
2013: 17 drugs
Part D drugs prescribed in 2013
Humira
15
$38,783
$2,586
Xifaxan
18
$35,163
$1,953
Creon
21
$28,830
$1,373
Aciphex
23
$14,959
$650
Lialda
24
$13,608
$567
Nexium
18
$5,943
$330
Apriso
14
$2,741
$196
Omeprazole
67
$1,694
$25
Peg-3350 With Flavor Packs
65
$1,236
$19
Sulfazine Ec
15
$1,034
$69
Gavilyte-N
23
$378
$16
Atorvastatin
17
$309
$18
Diltiazem Er
12
$278
$23
Trilyte With Flavor Packets
12
$217
$18
Famotidine
12
$179
$15
Zolpidem
13
$95
$7
Folic Acid
11
$36
$3
Money from drug and device companies
$22,026 in 2025
Industry payments by year
2025
1
5
$22,000
$22,026
2024
1
6
$55,550
$55,550
2023
1
2
$43,888
$43,888
2020
1
11
$48,150
$48,150
2019
2
14
$127,325
$131,435
Paid work is consulting, speaking, honoraria and royalties, as opposed to meals and travel.