Table 5.
Diagnostic accuracy characteristics of stepwise screening strategy
| Test | Sensitivity % (95% CI) |
Specificity % (95% CI) |
PPV % (95% CI) |
NPV % (95% CI) |
LR+ (95% CI) |
LR− (95% CI) |
Overall accuracy % (95% CI) |
|---|---|---|---|---|---|---|---|
| ALT ≥ 40 and US ≥ 2 n = 15 |
33 (19–49) |
98 (90–100) |
93 (66–99) |
65 (61–70) |
18.0 (2.5–133.3) |
0.7 (0.6–0.9) |
70 (60–79) |
| ALT < 40 and US ≥ 2 n = 44 |
63 (47–77) |
70 (56–81) |
61 (50–72) |
71 (61–79) |
2.1 (1.3–3.3) |
0.5 (0.4–0.8) |
67 (56–76) |
| ULN ≤ ALT < 40 and US ≥ 2 n = 40 |
56 (40–71) |
71 (78–83) |
60 (48–71) |
68 (59–75) |
2.0 (1.2–3.2) |
0.6 (0.4–0.9) |
65 (54–74) |
| ALT ≥ ULN and US ≥ 2 n = 30 |
44 (29–60) |
80 (68–90) |
63 (48–76) |
65 (58–72) |
2.3 (1.2–4.2) |
0.7 (0.5–0.9) |
65 (54–74) |
ULN = 22 IU/L for girls, 26 IU/L for boys
ULN upper limit of normal, US ultrasound, ALT alanine aminotransferase, PPV positive predictive value, NPV negative predictive value, LR+ positive likelihood ratio, LR− negative likelihood ratio