Table 3.
Operating characteristic | Value | 95% CI |
---|---|---|
Prevalence (125 extremities) | 6.4% | |
Prevalence (73 patients) | 8.2% | |
Sensitivity | 100% | 74–100% |
Specificity | 95.8% | 91–98% |
LR+ | 23.4 | 9.9–55.1 |
LR− | 0 | 0–0.32 |
PPV | 61.5% | 35–84% |
NPV | 100% | 98–100% |
NPV¥ A range for the post-test probability of DVT was assumed based on the 95% CI for the NPV. Using this, the upper limit for 193 the LR– confidence interval could be estimated according to the Bayes theorem (LR = post-test odds/pre-test odds)