Diagnostic performances of GPR, APRI and Fib-4 in The Gambia using Fibroscan as a reference standard (n=721)*
| F0–1 vs F2–4 | F0–2 vs F3–4 | F0–3 vs F4 | ||||
|---|---|---|---|---|---|---|
| GPR | ||||||
| AUROC (95% CI) | 0.86 (0.82 to 0.90) | 0.86 (0.83 to 0.90) | 0.91 (0.87 to 0.96) | |||
| Cut-off values† | 0.32 | 0.32 | 0.56 | |||
| Sensitivity/specificity (%) | 77/75 | 78/75 | 76/93 | |||
| Correctly classified (%) | 75 | 75 | 91 | |||
| PPV/NPV (%) | 34/95 | 32/96 | 52/97 | |||
| Positive/negative LR | 3.1/0.3 | 3.0/0.3 | 10.6/0.3 | |||
| APRI | ||||||
| AUROC (95% CI) | 0.78 (0.73 to 0.84) | 0.80 (0.74 to 0.85) | 0.87 (0.80 to 0.93) | |||
| Cut-off values‡ | 0.5 | 1.5 | 1.0 | 2.0 | ||
| Sensitivity/specificity (%) | 70/72 | 41/99 | 70/96 | 55/99 | ||
| Correctly classified (%) | 72 | 90 | 93 | 95 | ||
| PPV/NPV (%) | 30/93 | 83/91 | 62/97 | 82/96 | ||
| Positive/negative LR | 2.5/0.4 | 28.3/0.6 | 16.3/0.3 | 44.7/0.5 | ||
| Indeterminate results (%) | 27 | 4 | ||||
| Fib-4 | ||||||
| AUROC (95% CI) | 0.75 (0.69 to 0.81) | 0.75 (0.69 to 0.81) | 0.85 (0.79 to 0.91) | |||
| Cut-off values§ | 1.45 | 3.25 | ||||
| Sensitivity/specificity (%) | 67/72 | 42/96 | ||||
| Correctly classified (%) | 71 | 89 | ||||
| PPV/NPV (%) | 27/93 | 63/91 | ||||
| Positive/negative LR | 2.4/0.5 | 10.9/0.6 | ||||
| Indeterminate results (%) | 25 | |||||
| Comparison of AUROC | ||||||
| GPR and APRI | p=0.0004 | p=0.0003 | p=0.005 | |||
| GPR and Fib-4 | p<0.0001 | p<0.0001 | p=0.003 | |||
| APRI and Fib-4 | p=0.1 | p=0.03 | p=0.4 | |||
*The cut-off values for GGT were 58 and those for AST were 46 in men and 25 in women.
†Predetermined cut-off values of GPR were used.
‡Predetermined cut-off values of APRI were used (0.5 and 1.5 to distinguish significant fibrosis, and 1.0 and 2.0 to distinguish cirrhosis).
§Predetermined cut-off values of Fib-4 were used (1.45 and 3.25 to distinguish extensive fibrosis).
APRI, aspartate transaminase-to-platelet ratio index; AST, aspartate transaminase; AUROC, area under the receiver operating characteristic curve; GPR, gamma-glutamyl transpeptidase to platelet ratio; LR, likelihood ratio; NPV, negative predictive value; PPV, positive predictive value.