Scale readings | |||||
---|---|---|---|---|---|
Reference Hb (g/dl) | <6 | 6 to <8 | 8 to <10 | 10 to <12 | 12 or more |
FN, false negative; FP, false positive; LR, likelihood ratio; NPV, negative predictive value; PPV, positive predictive value; TN, true negative; TP, true positive. | |||||
<6 | 34 | 2 | 0 | 0 | 0 |
6 to <8 | 2 | 27 | 5 | 0 | 0 |
8 to <10 | 0 | 3 | 87 | 8 | 3 |
10 to <12 | 0 | 0 | 4 | 74 | 36 |
12 or more | 0 | 0 | 0 | 9 | 254 |
TP | 34 | 27 | 87 | 74 | 254 |
FP | 2 | 5 | 9 | 17 | 39 |
FN | 2 | 7 | 14 | 40 | 9 |
TN | 509 | 508 | 438 | 396 | 245 |
Sensitivity (%) | 94.4 | 79.4 | 86.0 | 64.9 | 96.6 |
Specificity (%) | 99.6 | 99.0 | 98.0 | 95.9 | 86.3 |
PPV (%) | 94.4 | 84.3 | 90.6 | 81.3 | 86.7 |
NPV (%) | 99.6 | 98.6 | 96.9 | 90.8 | 96.5 |
LR | 0.94 | 0.78 | 0.84 | 0.61 | 0.83 |