CALCULATED RISK The online tool offers predictions of post-op complications.

The American College of Surgeons' popular Surgical Risk Calculator is fairly accurate when it comes to estimating a patient's likelihood of suffering post-op complications, though a new update could boost its precision even further, according to a new study.

The online risk calculator was created in 2013 to give surgeons and patients a customized risk estimate for surgery. Surgeons can input information about a procedure and the patient's characteristics, and the calculator will determine that patient's individualized risk of suffering common post-op complications such as SSIs and deep vein thrombosis.

In a new study, researchers tested the calculator's accuracy by analyzing the agreement between predicted risks and actual outcomes. The researchers tested the calculator's accuracy by studying 2.7 million surgical records collected from 586 hospitals. They then tried tweaking the calculator's formulas to see how the adjustments impacted its overall accuracy.

The researchers found that before this recalibration, the calculator was largely accurate, but had a slight tendency to overestimate risk for the lowest- and highest-risk patients, and underestimate risks for patients at moderate danger of suffering post-op complications. The formula update seemed to solve these issues, the study's authors say, and will be added to the live version of the calculator later this fall or early next year.

"Our study demonstrates that the Surgical Risk Calculator has excellent calibration," says Mark E. Cohen, PhD, statistical manager in the ACS Division of Research and Optimal Patient Care and co-developer of the calculator. "Although no such tool can provide perfect predictions, the calculator does what it is intended to do — accurately estimate a patient's probabilities for important adverse events postoperatively."

Kendal Gapinski