Ambulatory surgery center sources and methodology
This page identifies the public information imported by the automated guide, explains the guide-created colored summary, and describes important limits.
Primary public sources
The consumer-facing CMS source for facility quality and patient-experience information.
The automated guide imports facility-level ASC quality measures, national benchmark values, and OAS CAHPS patient-experience results from current downloadable data.
Program requirements, measure information, reporting rules, and updates.
Standardized patient-experience survey information, administration guidance, and technical resources.
Public ASC results that may include CMS measures, voluntary Leapfrog ASC Survey results, transparency status, and Top ASC recognition. The guide provides a separate worksheet because Leapfrog results are not part of the guide-created CMS summary.
Current measure descriptions and scoring context for patient rights, preventing harm, medication safety, elective outpatient surgery, complex surgery, and patient experience.
Verify whether the exact ASC location is accredited or holds an additional certification.
Search organizations accredited through an ambulatory healthcare accreditation program.
Search for or request verification of QUAD A accreditation.
Measures used by the guide
General measures can include patient burns, falls, wrong-patient/site/side/procedure/implant events, hospital transfer or admission, appropriate temperature after anesthesia, colonoscopy follow-up recommendations, cataract visual improvement, and unplanned additional eye surgery. Procedure-related hospital-visit measures are used when CMS reports them for colonoscopy, orthopedics, urology, or general surgery.
OAS CAHPS results may include facilities and staff, communication about the procedure, patients’ overall rating of the facility, willingness to recommend, survey dates, completed surveys, and response rate. Missing and suppressed results remain missing.
No CMS overall ASC star: CMS does not assign ASCs an overall 1–5 quality star comparable to the overall ratings displayed for hospitals or nursing homes. The guide does not create a star.
How the guide-created summary works
The shape is a transparent summary of findings, not a CMS rating, clinical recommendation, endorsement, or declaration that a center is safe or unsafe.
| Summary | Rule used by the guide |
|---|---|
| Green circle | A relevant procedure comparison is available and is not unfavorable; at least two general safety rates are reported; and the defined red or yellow findings are absent. |
| Yellow triangle | A reported fall rate is above zero, the transfer/admission rate exceeds the reported national benchmark, or available information does not meet the requirements for green. |
| Red octagon | A reported patient-burn or wrong-patient/site/side/procedure/implant rate is above zero, or the selected procedure-related hospital-visit result is categorized as worse than the national benchmark. |
| Gray square | A usable CMS result matching the selected procedure is unavailable, suppressed, too small, or not published. Missing information never supports green. |
For cataract or eye surgery, the guide compares available visual-improvement and unplanned-additional-surgery rates with national benchmarks. Other procedure categories without a matching CMS outcome receive gray even when the center performs that procedure.
Important limitations
Public data describe a past reporting period and may not reflect recent staffing, ownership, clinical changes, or every outcome that matters. Small numbers can be unstable or suppressed. The measures do not establish that a particular patient is appropriate for outpatient surgery.
Compare the exact facility, not merely a health system or brand. Confirm surgeon experience, anesthesia coverage, infection prevention, emergency-transfer arrangements, accreditation or certification, insurance network status, separate bills, and current results directly.
How Leapfrog information is handled
The Leapfrog worksheet is completed by the visitor and is kept separate from the automated CMS summary. Leapfrog may display underlying CMS measures as well as information voluntarily submitted through its ASC Survey. A result shown on both sites should not be counted twice as independent evidence.
Leapfrog ASC results are not the A–F Leapfrog Hospital Safety Grade. “Did not report” does not by itself prove poor care, but patients may reasonably ask why information is unavailable and whether the center will provide current results. A Top ASC designation or favorable individual measures do not replace confirming the surgeon, procedure, anesthesia plan, emergency-transfer capability, and personal clinical risks.
How accreditation information is handled
The accreditation worksheet is completed by the visitor and is not included in the guide-created CMS summary. The Joint Commission, AAAHC, and QUAD A accredit ambulatory facilities; the applicable accreditor can differ by center. Accreditation reflects review against defined standards but is not an outcome rating, guarantee of safety, or determination that outpatient surgery is appropriate for an individual.
Last methodology review: September 23, 2026.
Return to the ASC comparisonSelected procedure measures and their limits
This guide uses checked CMS measure definitions, not a claim that all procedure data or facility results are validated. Colonoscopy maps to ASC-12 (7-day risk-standardized unplanned hospital visits per 1,000 procedures); ASC-9 concerns appropriate follow-up screening recommendations. Colonoscopy results are not used for other endoscopy. Cataract surgery uses ASC-11 (voluntary reporting of visual-function improvement within 90 days) and ASC-14 (unplanned anterior vitrectomy during cataract surgery, not all later additional surgery).
ASC-17, ASC-18, and ASC-19 cover orthopedic, urologic, and general surgery groups. They are not exact-operation rates; no separate ASC hip- or knee-replacement result is inferred. Missing, blank, suppressed, or nonnumeric rates are unavailable, never zero. Compare measures only within their defined setting, population, units, and periods. A CMS file year is not the measurement period.
CMS ASC facility data · CMS ASC measure descriptions · CMS collection periods
Information beyond the automated report
Public reporting does not cover every condition, service, or procedure. Detailed information may be collected in a facility’s own systems or specialty clinical registries, with different public-access limits. The hospital Sources page explains selected specialty registries and which offer public reports. These examples mainly concern hospital and procedural care; they are not a comprehensive list of resources for every care setting. Participation alone is not a quality rating.