Sensitivity and specificity of the checklist for different cut off scores
| Cut off score | Sensitivity (95% CI) | Specificity (95% CI) |
| ⩾3 | 1.00 (0.87–1.00) | 0.27 (0.18–0.39) |
| ⩾4 | 0.89 (0.71–0.98) | 0.43 (0.32–055) |
| ⩾5 | 0.70 (0.50–0.86) | 0.69 (0.57–0.79) |
| ⩾6 | 0.56 (0.35–0.75) | 0.88 (0.79–0.95) |
| ⩾7 | 0.33 (0.17–0.54) | 0.94 (0.86–0.98) |
| ⩾8 | 0.19 (0.06–0.38) | 0.95 (0.87–0.99) |
| ⩾9 | 0.11 (0.02–0.29) | 0.99 (0.93–1.00) |