Diagnostic performance of Ottawa SAH Rule
| Study | N | Sens (%) | 95% CI | Spec (%) | 95% CI | FNR (%) | 95% CI | FPR (%) | 95% CI |
| Perry et al 21 | 2131 | 100 | 100 to 100 | 15.3 | 13.7 to 16.8 | 0.0 | 0.0 to 0.0 | 84.7 | 83.2 to 86.3 |
| Bellolio et al 13 | 454 | 100 | 100 to 100 | 7.6 | 5.17 to 10.1 | 0.0 | 0.0 to 0.0 | 92.4 | 89.9 to 94.8 |
| Yiangou et al 25 | 162 | 100 | 100 to 100 | 38.7 | 31.4 to 46.6 | 0.0 | 0.0 to 0.0 | 61.0 | 53.4 to 68.6 |
| Cheung et al 14 | 500 | 94.0 | 87.4 to 100 | 32.9 | 28.5 to 37.2 | 6.0 | 0.0 to 12.6 | 67.1 | 62.8 to 71.5 |
| Chu et al 15 | 137 | 100 | 100 to 100 | 22.4 | 15.3 to 29.4 | 0.0 | 0.0 to 0.0 | 77.6 | 70.6 to 84.7 |
| Pathan et al 19 | 145 | 100 | 100 to 100 | 44.3 | 36.1 to 52.5 | 0.0 | 0.0 to 0.0 | 55.7 | 47.5 to 63.9 |
| Wu et al 24 | 913 | 100 | 100 to 100 | 37.0 | 33.8 to 40.1 | 0.0 | 0.0 to 0.0 | 63.0 | 59.9 to 66.2 |
| Perry et al 23 | 3672 | 100 | 100 to 100 | 12.7 | 11.6 to 13.9 | 0.0 | 0.0 to 0.0 | 87.3 | 86.1 to 88.4 |
| Pooled (n=8) | 8114 | 99.5 | 90.8 to 100 | 23.7 | 15.5 to 34.4 | 0.49 | 0.00 to 9.2 | 76.3 | 65.6 to 84.5 |
FNR, false negative rate; FPR, false positive rate; N, number; Sens, sensitivity; Spec, specificity.