Table 2 CTA studies categorised by true/false positive/negative and bleeding site
Upper gastro-intestinal bleeding (n = 34) | Lower gastro-intestinal bleeding (n = 26) | Renal (n = 11) | Liver (n = 17) | Abdominal / pelvic wall (n = 17) | Other extra-luminal sites (n = 50) | p | |
|---|---|---|---|---|---|---|---|
False negative | 3 (9%) | 0 | 4 (36%) | 0 | 1 (6%) | 0 | < 0.001 |
True negative | 3 (9%) | 2 (8%) | 1 (9%) | 0 | 0 | 0 | 0.09 |
False positive | 4 (12%) | 6 (23%) | 0 | 2 (12%) | 1 (6%) | 9 (18%) | 0.46 |
True positive | 24 (71%) | 18 (69%) | 6 (54%) | 15 (88%) | 15 (88%) | 41 (82%) | 0.18 |
Sensitivity | 89% | 100% | 60% | 100% | 94% | 100% | |
Specificity | 43% | 25% | 100% | NA | NA | NA | |
Positive predictive value | 85% | 75% | 100% | 88% | 94% | 82% | |
Negative predictive value | 51% | 100% | 20% | NA | NA | NA |