Patients undergoing noncardiac surgery requiring overnight hospital stay.
Overall assessment: A well-performing risk calculator developed in a larger international study.

Prediction accuracy: Very good (c-statistic 0.84 in bootstrap internal validation and 0.85 in development).

Risk to reproducibility: Low. The model was developed and internally validated in a large international sample.

Risk of data reporting bias: Low. Few patients had missing data and appropriate statistical imputation was used.

Risk to transportability: Low. The model was developed using prospectively collected data from multiple countries.