Hospitals participating in ACS NSQIP significantly improve surgical outcomes over time.
http://journals.lww.com/annalsofsurgery/Abstract/publishahead/Improved_Surgical_Outcomes_for_ACS_NSQIP_Hospitals.97468.aspx
http://www.eurekalert.org/pub_releases/2015-02/acos-hpi022715.php
"ACS NSQIP is a nationally validated, risk-adjusted, outcomes-based program designed to measure and improve the quality of surgical care in participating hospitals. The program employs prospective, peer-controlled, validated clinical data collection to quantify 30-day surgical outcomes and allows comparisons of outcomes among all participating hospitals.
The new study by the American College of Surgeons research team found that among hospitals currently participating in the program 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)."