Table 1 D-dimer assay and CTPA sensitivity, specificity and predictive values (95% confidence intervals)
| Â | D-dimer assay: Results based on number of positive CTPA results | CTPA | |
|---|---|---|---|
| Â | N = 41 (initial results) | N = 36 (results after specialist review) | N = 405 |
Sensitivity | 95.1 (82.2-99.2) | 100 (88.0-100) | x |
Specificity | 16.0 (11.1-22.5) | 16.7 (11.7-23.1) | 98.5 (96.4-99.5) |
Positive predictive value | 21.0 (15.5-27.7) | 19.4 (14.1-25.9) | 92.4 (82.5-97.2) |
Negative predictive value | 93.3 (76.5-98.8) | 100 (85.9-100) | x |