Table 2.
Sensitivity and specificity at various thresholds of caffeine intake for detection of children reporting fewer than 9 h of sleep.
| Caffeine Threshold (mg/kg/day) | Detection of Children Reporting < 9 h of Sleep Per Night |
||
|---|---|---|---|
| Sensitivity | Specificity | Youden J-Index * | |
| 0.01 | 0.99 | 0.01 | 0.00 |
| 0.05 | 0.79 | 0.30 | 0.09 |
| 0.10 | 0.66 | 0.45 | 0.11 |
| 0.25 | 0.41 | 0.68 | 0.09 |
| 0.50 | 0.26 | 0.82 | 0.08 |
| 1.00 | 0.14 | 0.91 | 0.05 |
| 1.50 | 0.08 | 0.95 | 0.02 |
| 2.00 | 0.05 | 0.97 | 0.01 |
| 2.50 a | 0.03 | 0.98 | 0.01 |
| 3.00 b | 0.02 | 0.99 | 0.01 |
a = Health Canada recommended threshold; b = European Food Safety Authority recommended threshold; * J = (sensitivity + specificity − 1).