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Not medical advice. This page explains a hospital quality program and a public estimation tool. It does not tell any patient what their own risk is or what to do about it; that conversation belongs with the surgical team.
NSQIP is the American College of Surgeons National Surgical Quality Improvement Program. It is a registry in which participating hospitals record clinical details of surgical patients, track outcomes for 30 days, and receive risk-adjusted comparisons. The public Surgical Risk Calculator is a separate tool built on that registry’s data. This guide separates the two, explains what risk adjustment means here, and shows where NSQIP sits next to related quality systems (American College of Surgeons pages, checked 2026-11-07).
What NSQIP stands for and what it is
NSQIP stands for National Surgical Quality Improvement Program; the current program is branded ACS NSQIP. The College describes it as a variable-based data registry used to improve quality across surgical departments in acute care hospitals and ambulatory surgery centers. The data come from the patient’s medical chart, not from insurance claims.
Two parts are easy to confuse:
- The program (registry): a hospital enrols, collects data, and receives reports. Its audience is surgeons, quality staff and administrators.
- The Surgical Risk Calculator: a public web tool that estimates the chance of an unfavourable outcome after surgery. Its estimates come from ACS NSQIP data on patients who had a similar procedure. The search term “NSQIP risk calculator” refers to this tool.
Who runs it and what it covers
The American College of Surgeons (ACS) runs the program. “ACS surgery” is not a type of operation: ACS here means the College, which is also the body behind its surgical quality programs.
According to the College’s history page, the program began in the Veterans Affairs system. In the mid to late 1980s Congress required the VA to report risk-adjusted surgical outcomes. The National VA Surgical Risk Study ran from 1991 to 1993 across 44 centers, and the VA NSQIP launched in 1994. A 1999 pilot involved three non-federal hospitals, and a 2001 pilot funded by the Agency for Healthcare Research and Quality involved 18 private hospitals. The ACS began enrolling private-sector hospitals in 2004. By 2010 the College reported nearly 700 adult hospitals across 49 states and the District of Columbia, plus more than 150 hospitals in 18 other countries.
The College describes vascular and emergency general surgery modules, and its related programs include ACS NSQIP Pediatric and MBSAQIP (bariatric and metabolic surgery). Hospital and registry access run through the ACS Quality Portal and the ACS NSQIP Registry.
Is NSQIP risk adjusted?
Yes. The College states that results are risk-adjusted and case mix-adjusted, which lets a hospital make a like-for-like (“1:1”) comparison with other hospitals. In practice this rests on three design choices described by the College:
- Clinical data are abstracted from the patient chart rather than taken from billing claims.
- A hospital trains and tests a Surgical Clinical Reviewer (SCR) who collects the data.
- Patients are followed for 30 days after surgery, so complications after discharge are captured.
The same idea underlies other quality metrics, such as the standardized infection ratio: a raw count of events says little until it is set against what would be expected for the patients and procedures involved. The Donabedian model classifies this kind of measure as an outcome measure.
What is risk stratification in surgery?
Risk stratification means sorting patients into groups by how likely an unfavourable outcome is, based on information known before surgery, so that results can be compared fairly or planning can reflect the risk. This is a plain-language definition rather than a College quotation. NSQIP reports use it at hospital level (adjusting comparisons), while the risk calculator applies it to an individual set of preoperative inputs. A much simpler, older stratification is the anaesthesiologist’s ASA physical status classification.
How the Surgical Risk Calculator works
The calculator estimates the chance of a complication or death after surgery from preoperative information, using ACS NSQIP data on patients with similar procedures. The tool opens with a multi-step flow and asks users to accept a disclaimer first. The disclaimer states that estimates are not guarantees, may omit risk factors, and do not replace a doctor’s advice. ACS also asks that the tool not be embedded or automated; it may be opened in a new window with ACS branding unaltered.
What are the potential risks associated with surgery?
Risks depend on the patient, the procedure and the setting, so no single list applies. NSQIP is a way of measuring complications and deaths after surgery; it does not itself predict what will happen to one person.
How to find and use NSQIP resources
The College’s ACS NSQIP page is the starting point. From it:
- Open the ACS NSQIP page on facs.org under Quality Programs, Data and Registries.
- Use the Surgical Risk Calculator link for the public tool.
- Use Find a Hospital to see participating hospitals.
- Hospitals interested in joining use the Apply for ACS NSQIP page.
- Enrolled hospitals reach data entry and reports through the ACS NSQIP Registry and manage hospital information in the ACS Quality Portal; both sign-in links are on the ACS NSQIP page.
- Reviewers train and test through the SCR Training and Testing link on the same page.
Strengths and limits
- Strength: chart-abstracted clinical data, a trained reviewer and 30-day follow-up give richer information than claims data.
- Strength: the case-mix and risk adjustment allow comparison between hospitals with different patient populations.
- Limit: it is a participation program. The College’s page lists no eligibility criteria or fees and refers hospitals to its application page, so cost and requirements must be obtained from the College.
- Limit: hospital-level registry reports are for participants; the public sees the calculator and the participating-hospital finder, not each hospital’s results.
- Limit: the calculator’s own disclaimer says estimates are not guarantees and may omit risk factors.
Related systems
| System | What it is | How it differs from ACS NSQIP |
|---|---|---|
| ACS NSQIP Pediatric, MBSAQIP, vascular and emergency general surgery modules | Modules and related programs named by the College | Same program family, aimed at specific populations or specialties |
| CDC NHSN | CDC surveillance system for healthcare-associated infections | Focused on infection events and standardized infection ratios rather than all surgical complications |
| ASA physical status | Anaesthesiologist’s preoperative grade of a patient’s health | A single grade, not a registry or outcome comparison |
| Leapfrog Hospital Survey | Voluntary hospital safety and quality survey | A separate survey program, not the NSQIP registry |
FAQ
What does NSQIP stand for?
National Surgical Quality Improvement Program, run by the American College of Surgeons as ACS NSQIP.
What is ACS surgery?
It is not a procedure. ACS means the American College of Surgeons, which runs the NSQIP quality program and the Surgical Risk Calculator.
Is NSQIP risk adjusted?
Yes. The College states that results are risk-adjusted and case mix-adjusted for comparison between hospitals.
Is the NSQIP risk calculator the same as NSQIP?
No. The calculator is a public tool whose estimates are derived from ACS NSQIP data; the registry itself is a hospital program.
Can the risk calculator replace advice from a surgeon?
No. Its disclaimer says the estimates do not replace a doctor’s advice.
Sources
- American College of Surgeons, ACS NSQIP, checked 2026-11-07.
- American College of Surgeons, History of ACS NSQIP, checked 2026-11-07.
- American College of Surgeons, ACS Surgical Risk Calculator, checked 2026-11-07.
