What was the quality of the clinical evidence for the risk tools?
The review included 7 risk tools that were validated in a range of heart failure cohorts. Overall, the quality of the evidence ranged from very low to high, and varied significantly between the tools. Many of the studies included in the review reported the area under the curve (AUC) or c-statistic as the only accuracy data. The committee noted that this metric enabled comparison of the overall accuracy of the tools, and agreed a priori that a minimum AUC of 0.70 would be necessary to consider recommending a tool, but that AUC itself was unlikely to provide enough information to make a recommendation. For those tools where multiple studies reported the AUC in different cohorts, the results were inconsistent, with some studies suggesting an AUC of greater than 0.70, and others estimating a lower accuracy. Many studies also did not report calibration data and these were downgraded for risk of bias.