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Fonteum Care Compare · California

California ambulatory surgical centers: 645 Medicare-certified, ASC quality measures with NPI bridge.

Per-facility ASC-1 through ASC-12 quality measures with deterministic NPI bridge (100.0% NPI coverage in California) — the only Care Compare facility type with a usable provider-identity join key.

Cross-check at Medicare.gov →All states →
Snapshot May 7, 2026·645 Medicare-certified ASCs in California · 100.0% with NPI·CMS Care Compare — ASC Quality (4jcv-atw7)·Module overview →·Methodology →·Audit Pack →
Source-modified 2025-12-16 · Reporting year 2024 · ASC-12 hospital-visit follow-up rates suppressed for facilities below volume threshold

Editorial note: California has dense local journalism + Leapfrog coverage of outpatient surgery; Fonteum's contribution is the per-facility ASC-1-12 + NPI data layer, not editorial commentary.

ASC-12 performance breakdown — California

ASC-12 measures hospital-visit rate within 7 days of outpatient surgery. CMS-published performance categories on facilities meeting the volume threshold.

N/A
372
No Different Than the National Rate
241
Number of Cases Too Small
27
Better Than the National Rate
3

ASC-1 through ASC-11 quality measures — California state means

Each row is the mean CMS-published rate across Californiafacilities that meet the measure’s reporting threshold. Lower is better for adverse-event measures; higher is better for the prophylactic-antibiotic process measure. Facilities CMS suppressed for low case volume are excluded from the mean, not counted as zero.

MeasureDirectionState meanFacilities reporting
Patient burn rateLower is better0.00%284
Unplanned hospital transfer/admissionLower is better0.02%327
Wrong site, side, patient, or procedureLower is better0.00%294
All-cause hospital readmission rateLower is better0.08%363
Appropriate prophylactic antibiotic useHigher is better78.99%209
Cataract surgery complication rateLower is better80.62%24

Highest-volume ASCs — California

Top 25 by ASC-12 reportable case volume (a procedural-volume signal, not a quality measure).

FacilityCityASC-12 casesCategory
Monterey bay endoscopy center llcMONTEREY6275No Different Than the National Rate
Mirage endoscopy center lpRANCHO MIRAGE6258Better Than the National Rate
Fresno ca endoscopy asc lpFRESNO5773No Different Than the National Rate
Santa maria digestive diagnostic centerSANTA MARIA5351No Different Than the National Rate
Sansum clinicSANTA BARBARA4865No Different Than the National Rate
Redding endoscopy centerREDDING4739No Different Than the National Rate
Pasadena endoscopy center incPASADENA4461No Different Than the National Rate
Sutter roseville endoscopy centerROSEVILLE4017No Different Than the National Rate
San francisco endoscopy center llcSAN FRANCISCO3966No Different Than the National Rate
Hoag endoscopy centerNEWPORT BEACH3830No Different Than the National Rate
Sierra endoscopy centerGRASS VALLEY3593No Different Than the National Rate
East bay endosurgeryOAKLAND3476No Different Than the National Rate
Palo alto medical foundation camino surgery divisionMOUNTAIN VIEW3466No Different Than the National Rate
Newport beach orange coast endoscopyNEWPORT BEACH3402No Different Than the National Rate
Glbesc llc dba memorialcare outpatient surgical center long beachLONG BEACH3364Better Than the National Rate
Surgecenter of palo altoPALO ALTO3301No Different Than the National Rate
Folsom sierra endoscopy centerFOLSOM3171No Different Than the National Rate
Hoag endoscopy center irvineIRVINE3094No Different Than the National Rate
Truxtun surgery center incBAKERSFIELD3081No Different Than the National Rate
Aspen surgery center llc dba aspen surgery centerWALNUT CREEK2955No Different Than the National Rate
Mid peninsula endoscopyBURLINGAME2882No Different Than the National Rate
The endoscopy centerYUBA CITY2865No Different Than the National Rate
Los robles surgicenter llcTHOUSAND OAKS2824No Different Than the National Rate
Golden gate endoscopy center llcSAN FRANCISCO2773No Different Than the National Rate
Valley endoscopy centerTARZANA2678No Different Than the National Rate

California ambulatory surgical centers — FAQ

How many ambulatory surgical centers are Medicare-certified in California?
645 Medicare-certified ambulatory surgical centers operate in California as of the CMS Care Compare ASC Quality snapshot (2026-05-07). Every facility carries a National Provider Identifier — ASCs are the only Care Compare facility type with a 100% deterministic NPI bridge.
What ASC quality measures does California report?
CMS publishes ASC-1 through ASC-12. This page aggregates the state mean for the per-facility rate measures that have at least one reporting facility in California, plus the ASC-12 colonoscopy follow-up performance category. Measures are CMS-published rates: lower is better for adverse-event measures (burns, transfers, wrong-site events, readmissions, cataract complications) and higher is better for appropriate prophylactic antibiotic use.
Why are some facilities missing a quality rate?
CMS suppresses a measure when a facility falls below the minimum case volume for that measure in the reporting window. Suppressed facilities are excluded from each state mean rather than counted as zero, so the averages reflect only facilities CMS actually scored.
Where does this ASC data come from and how current is it?
All columns trace to the CMS Care Compare Ambulatory Surgical Center Quality dataset (PDC 4jcv-atw7), source-modified 2025-12-16. Fonteum redistributes the public-domain CMS file without alteration and links every row to its provenance record; cross-check any facility at Medicare.gov.

Compare other facility types

Every Fonteum Care Compare module carries the same per-facility provenance for California and the rest of the country.

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Reviewed by Jennifer Montecillo, MD, medical reviewer. Non-practicing medical reviewer.

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Reviewed by Jennifer Montecillo, MD, medical reviewer. Non-practicing medical reviewer.

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