American College Of Surgeons - Inspiring Quality: Highest Standards, Better Outcomes

Key Studies

A growing number of peer-reviewed studies show that the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP®) helps hospitals achieve measurable improvements in quality of care.

Improves Outcomes, Reduces Complications and Saves Money

A study published in the February 2015 edition of the Annals of Surgery found that among hospitals currently participating in the ACS NSQIP for at least three years, 69 percent reduced the rate of death; 79 percent reduced the rate of complications; and 71 percent reduced the rate of surgical site infections. It was estimated that, on average, these hospitals reduced their rate of death by 0.8 percent per year; reduced their rate of complications by 3.1 percent per year; and reduced their rate of surgical site infection by 2.6 percent per year (with respect to the prior year’s rates). Because these are annual reductions, hospitals committed to participation in the program can see significant improvement accumulate over time.

Cohen ME1, Liu Y, Ko CY, et al. "Improved Surgical Outcomes for ACS NSQIP Hospitals Over Time: Evaluation of Hospital Cohorts With up to 8 Years of Participation." Ann Surg. DOI: 10.1097/SLA.0000000000001192.

A study published in 2012 in the Journal of the American College of Surgeons found that a 10-hospital collaborative in Tennessee, called the Tennessee Surgical Quality Collaborative, successfully reduced complications and saved $2.2 million per 10,000 cases from 2009 to 2010. Hospitals saw improvement in superficial surgical site infection (18.9 percent reduction), acute renal failure (25.1 percent reduction), graft/prosthesis/flap failure (60.5 percent reduction), ventilator longer than 48 hours (14.7 percent reduction) and wound disruption (34.3 percent) during this time period. Because ACS NSQIP cases are sampled, the collaborative projects it saved at least $8 million from 2009 to 2010.

Guillamondegui OD, Cofer JB, et. al. “Using the National Surgical Quality Improvement Program and the Tennessee Surgical Quality Collaborative to Improve Surgical Outcomes.” Journal of the American College of Surgery. 2012.

A study published in the September 2009 issue of the Annals of Surgery evaluated 118 hospitals that began participating in ACS NSQIP between 2005 and 2007. The study showed that hospitals participating hospitals each prevented 250 to 500 complications annually. The study also concluded that hospitals of all types – large and small, urban and rural, teaching and non-teaching – improved their quality of care through ACS NSQIP, and the hospitals that were poorer performers when they joined ACS NSQIP, achieved the greatest quality improvement.

Hall BL., et al. “Does Surgical Quality Improve in the American College of Surgeons National Surgical Quality Improvement Program.”  Annals of Surgery. 250(3):363-376; Sept. 2009.

Quality improvement initiatives save money by reducing complications and length of stay. One study recaps two such cases in which initiatives were implemented after review of ACS NSQIP data: Surrey Memorial Hospital in Vancouver, British Columbia, saved about $2.5 million by reducing the rate of surgical site infections (SSIs) over a two-year period while Henry Ford Hospital in Detroit, Mich., saved about $2 million by reducing patient length of stay by an average of 1.54 days.

Ingraham AM, Richards KE, Hall BL, Ko CY. “Quality Improvement in Surgery: the American College of Surgeons National Surgical Quality Improvement Program Approach.” Advances in Surgery. 44:251-267; Oct. 2010.

Answers the Call for Better Quality Measures

Research reveals that there is only a weak association between compliance with process measures and risk-adjusted outcomes. There is growing national interest in developing risk-adjusted, outcomes-based measures, including new measures based on ACS NSQIP endorsed by the National Quality Forum.  

Ingraham AM, Cohen ME, Bilimoria KY, Dimick JB, Richards KE, Raval MV, Fleisher LA, Hall BL, Ko CY. “Association of Surgical Care Improvement Project Infection-Related Process Measure Compliance with Risk-Adjusted Outcomes: Implications for Quality Measurement.” Journal of the American College of Surgery. 211: 705-714; 2010.

Ingraham AM, Richards KE, Hall BL, Ko CY. “Quality Improvement in Surgery: the American College of Surgeons National Surgical Quality Improvement Program Approach.” Advances in Surgery. 44:251-267; 2010.

Uses Robust Clinical Data

ACS NSQIP Data is Highly Reliable & Accurate

A 2008 study in Surgery compared ACS NSQIP’s risk-adjusted, clinical, 30-day outcomes database with the administrative data collected in the University HealthSystems Consortium (UHC) program. Researchers found ACS NSQIP uncovered 26 percent more complications than the UHC program. Among surgical site infections (SSI), 11 percent of patients were reported to have had an SSI in the ACS NSQIP database while only one percent where identified in the UHC database.

In 2009, a study in the American Journal of Medical Quality directly compared the UHC database and the ACS NSQIP dataset, finding that ACS NSQIP data was more highly correlated to outcomes. The study found UHC’s program “missed or misclassified” several major complications due to its reliance on administrative data.

Steinberg S, Popa M, et al. “Comparison of Risk-Adjustment Methodologies in Surgical Quality Improvement.” Surgery. 144:662-669; 2008. 

Davenport DL, Holsapple CW, Conigliaro J “Assessing Surgical Quality Using Administrative and Clinical Data Sets: A Direct Comparison of the University HealthSystem Consortium Clinical Database and the National Surgical Quality Improvement Program Data Set.”  American Journal of Medical Quality. 24(5):395-402; Sept-Oct 2009.

Reduces Morbidity

A study published in the August 2008 issue of Annals of Surgery evaluated patients undergoing general or vascular surgery in 128 Veterans Affairs (VA) medical centers and 14 private sector hospitals between 2001 and 2004. The study showed that the implementation of ACS NSQIP in private sector hospitals was associated with a reduction in morbidity following major and general vascular surgery similar to what had previously been observed for eight surgical specialties in the VA.

Khuri S, Henderson W, Daley J, et al. “Successful Implementation of the Department of Veterans Affairs’ National Surgical Quality Improvement Program in the Private Sector: The Patient Safety in Surgery Study.” Annals of Surgery.  248:329-336; 2008.

Reduces Mortality

The ACS NSQIP started as a statistically reliable, risk-adjusted tool to help the Department of Veterans Affairs Hospitals measure their quality of care. A 2007 study showed that from 1991 to- 2006, the hospitals saw a 47 percent drop in postoperative mortality and a 43 percent drop in postoperative morbidity rates

Khuri S, et al. “The Patient Safety in Surgery Study: Background, Study Design, and Patient Populations.” Journal of the American College of Surgery. ;204:1089-1102; 2007.

Uses Highly Effective Training and Auditing Procedures

A study published in the January 2010 issue of the Journal of the American College of Surgeons evaluated the data quality and inter-rater reliability in ACS NSQIP for calendar years 2005 through 2008. The study determined the training and audit procedures for hospitals participating in ACS NSQIP are highly effective in collecting data. Audit results show that data have been reliable since the program’s inception and that reliability has improved every year.

Shiloach M, Frencher S, Steeger J, et al. “Toward Robust Information: Data Quality and Inter-Rater Reliability in the American College of Surgeons National Surgical Quality Improvement Program.” Journal of the American College of Surgery. 210; 6-16; 2010.

Includes Validated Measurements

A study published in the Journal of the American College of Surgeons assessed the validity of risk-adjusted surgical morbidity and mortality rates as measures of quality of care. The study confirmed an association between the risk-adjusted adverse outcomes of surgical mortality and postoperative morbidity.

Daley J, Forbes M, Young G, et al. “Validating Risk-Adjusted Surgical Outcomes: Site Visit Assessment of Process and Structure.” Journal of the American College of Surgery. 185:341-351; 1997.

Pays for Itself by Avoiding Just One Major Surgical Complication

Complications Missed by Administrative Data

A study of postoperative complications in a high-volume surgery center in Switzerland showed that the severity of complications had an impact on the hospital’s costs much greater than any other parameter. Studying 1,200 major surgery patients who underwent procedures such as liver/bile duct, pancreatic and colon resection operations, the authors concluded that the average cost of uneventful cases was $27,946 while the average cost of cases with grade IV complications was $159,345, a fivefold increase. As a result, avoiding just one major post-surgical complication per year will more than pay for a hospital’s ACS NSQIP program.

Vonlanthen R, Slankamenac K, Breitenstein S, Puhan MA, Muller MK, Hahnloser D, Hauri D, Graf R, Clavien P. “The Impact of Complications on Costs of Major Surgical Procedures.” Annals of Surgery. 254:907-913; 2011.