Validation of dipstick score to predict laboratory diagnosis of urinary tract infection (UTI).a
| Cut-off point on dipstick score (% at or above cut-off point) | Sensitivity, % | Specificity, % | PPV, % | NPV, % | % correctly classified | LR +ve test | LR –ve test |
|---|---|---|---|---|---|---|---|
| ≥0 (100) | 100 | 0 | – | – | 66 | 1 | – |
| ≥1 (84) | 94 | 37 | 74 | 76 | 75 | 1.5 | 0.2 |
| ≥1.5 (77) | 89 | 46 | 76 | 68 | 75 | 1.7 | 0.2 |
| ≥2 (61) | 75 | 66 | 81 | 57 | 72 | 2.2 | 0.4 |
| ≥2.5 (60) | 74 | 67 | 81 | 56 | 71 | 2.2 | 0.4 |
| ≥3 (24) | 33 | 94 | 92 | 42 | 54 | 6.1 | 0.7 |
| ≥3.5 (23) | 32 | 94 | 92 | 42 | 53 | 5.8 | 0.7 |
| ≥4.5 (19) | 26 | 95 | 91 | 40 | 49 | 5.3 | 0.8 |
| >4.5 (0) | 0 | 100 | – | – | 34 | – | 1 |
↵a Score weighted according to the rounded logistic coefficients based on the sum of nitrite = 2, leucocyte = 1.5, blood = 1. LR = likelihood ratio. NPV = negative predictive value. PPV = positive predictive value.