Sensitivity, specificity and negative predictive value of the Ottawa Subarachnoid Hemorrhage Rule (n = 1153)
| Assessment using Ottawa SAH Rule | Participants with SAH n = 67 | Participants without SAH n = 1086 |
|---|---|---|
| No. of positive results | 67 | 938 |
| No. of negative results | 0 | 148 |
| Sensitivity, % (95% CI) | 100.0 (94–100.0) | |
| Specificity, % (95% CI) | 13.6 (13.1–15.8) | |
| Negative predictive value, % | 100.0 | |
| +LR (95% CI) | 1.16 (1.13–1.19) | |
| −LR (95% CI) | 0 (NA) |
Note: CI = confidence interval, LR = likelihood ratio, NA = not available, SAH = subarachnoid hemorrhage.