Table 2

Sensitivity, specificity, and likelihood ratio for positive test result (LR+) for all possible cut off points

Cut off point (pg/ml)SensitivitySpecificityLR+
01.0000.0001.00
220.9740.5932.39
830.9740.8898.77
880.9490.8898.54
2400.9490.96325.62
13000.5380.96314.54
14000.5381.000
27500.0001.000