Table 3. Specificity and sensitivity of the different search strategies.
| Specificity a | Sensitivity b | |
|---|---|---|
| Monthly EMR search, location-restricted | 52% (540/1,042) | 54% (540/1,000) |
| Two-year comprehensive EMR search 1, location-restricted | 39% (792/2,011) | 79% (792/1,000) |
| Two-year comprehensive EMR search 2, location-restricted | 37% (798/2,155) | 80% (798/1,000) |
| Two-year comprehensive EMR search, location-unrestricted | 10% (978/9,935) | 98% (978/1,000) |
| All DUHS searches (electronic and manual) | – | 97% (1,000/1,028) |
Abbreviations: DUHS, Duke University Health System; DURHAM VAMC, Durham Veterans' Administration Medical Center; DVT, deep venous thrombosis; EMR, electronic medical record; PE, pulmonary embolism.
For the four EMR searches, specificity represents the number of “true positive” individuals (i.e., living in Durham County with new DVT/PE diagnosed during the surveillance period) over the total number of individuals identified by the specific search strategy.
For the four EMR searches, sensitivity represents the number of “true positive” individuals (i.e., living in Durham County with new DVT/PE diagnosed during the surveillance period) identified by each search strategy over the total number of individuals identified by all DUHS strategies combined (electronic and manual searches, and autopsy reports). For the fifth search, sensitivity represents the total number of individuals identified by DUHS strategies divided by the total number of individuals identified by all approaches (DUHS and DURHAM VAMC).