Adult patients having elective noncardiac surgery requiring hospital stay.
Overall assessment: High quality

Prediction accuracy: Fair. C-statistic was in the 0.70-0.80 range in multiple external validation studies.

Risk to reproducibility: Low. The model was externally validated in multiple high-quality studies.

Risk of data reporting bias: Low. There was minimal missing predictor and outcome data in the high-quality validation studies.

Risk to transportability: Low. The model was externally validated in multiple high-quality studies in different geographical regions.
Original publication: Lee TH, Marcantonio ER, Mangione CM, Thomas EJ, Polanczyk CA, Cook EF, Sugarbaker DJ, Donaldson MC, Poss R, Ho KK, Ludwig LE, Pedan A, Goldman L. Derivation and prospective validation of a simple index for prediction of cardiac risk of major noncardiac surgery. Circulation. 1999 Sep 7;100(10):1043-9.

Risk estimates were derived from a guideline statement on the basis of high-quality external validation studies. These risk estimates are higher than those derived on the basis of the original data used to create the RCRI. The original RCRI study monitored creatine kinase muscle and brain isoenzyme and excluded emergency surgery patients, whereas high-quality external validation studies monitored the more sensitive troponin biomarkers and some included emergency surgery patients: Duceppe E, Parlow J, MacDonald P, Lyons K, McMullen M, Srinathan S, et al. Canadian Cardiovascular Society Guidelines on Perioperative Cardiac Risk Assessment and Management for Patients Who Undergo Noncardiac Surgery. Can J Cardiol. 2017 Jan;33(1):17–32.