Sensitivity, specificity, positive (PPV) and negative (NPV) predictive value of conventional bowel US and contrast enhanced bowel US in detecting one or more small bowel strictures as identified at barium x ray
| TP | TN | FP | FN | Sensitivity (95% CI) | Specificity (95% CI) | PPV | NPV | |
|---|---|---|---|---|---|---|---|---|
| TP, true positive; TN, true negative; FP, false positive; FN, false negative. | ||||||||
| *In this analysis a result was considered to be truly positive when at least one stricture, identified at US, was matched to a lesion seen at small bowel enteroclysis. In other words, each patient was classified simply as a carrier of small bowel stenosis if at least one of these lesions was revealed at x ray. | ||||||||
| Conventional bowel US | ||||||||
| At least one small bowel stricture* | 20 | 70 | 5 | 7 | 74.0% (72.1–75.8) | 93.3% (90.9–95.6) | 80.0% | 90.9% |
| Multiple strictures (two or more) | 5 | 86 | 5 | 4 | 55.5% (54.1–56.8) | 95.5% (93.1–97.8) | 50.0% | 95.5% |
| Contrast enhanced US | ||||||||
| At least one small bowel stricture* | 24 | 73 | 2 | 3 | 88.8% (86.5–91.0) | 97.3% (94.8–99.7) | 92.3% | 96.0% |
| Multiple strictures (two or more) | 7 | 89 | 2 | 2 | 77.7% (75.7–79.6) | 97.8% (95.3–100) | 77.7% | 97.8% |