The ATRIA stroke risk score was shown to have better overall accuracy, but although it had better specificity than CHA2DS2-VASc (fewer false-positive results) it had lower sensitivity, meaning that more people at risk would be missed (more false-negative results) compared with the CHA2DS2-VASc score. As already suggested, sensitivity was agreed by the committee to be more important than specificity because the risks of unnecessary anticoagulation are outweighed by the risks of not treating people who need anticoagulation. In addition, the ATRIA risk score may result in a time delay in calculating the results. The committee also discussed that the evidence for the QStroke risk calculator suggested that it might be a useful tool. However, the evidence was limited, and they agreed that further research was needed. How the recommendation might affect practice The recommendation does not constitute a change in practice, and so there would not be a resource impact on the NHS. Return to recommendations Bleeding risk Why the committee made the recommendations The committee agreed that anticoagulation should usually be considered in people at risk of stroke even if bleeding risk is high, and so a bleeding risk tool should not be used to provide a cut off for determining who should have anticoagulation. Instead, the tool should be used to provide accurate knowledge of absolute bleeding risk, which can support discussions between the person and their healthcare professional about bleeding risk modification and appropriate levels of vigilance. They therefore agreed that accurately estimating absolute risk (calibration) is more important than identifying a risk threshold for anticoagulation (discrimination) when choosing between different bleeding risk tools. The committee focused on calibration data for the tools with the most evidence: ORBIT, HAS-BLED and ATRIA. 