Are we taking a risk with risk assessment tools? Evaluating the relationship between NSQIP and the ACS risk calculator in colorectal surgery.

•Elective colorectal surgery had low correlation between the ACS Risk Calculator and NSQIP outcomes for quality outcomes.•There was poor overall predictive accuracy for the ACS Risk Calculator with actual outcomes.•There was poor overall predictive accuracy for NSQIP with actual outcomes.•These results have implications when using these tools for risk stratification and quality improvement.