Table 3.

Assay performance of Xpert Clostridium difficile and VIDAS Clostridium difficile A & B assays for the detection of toxigenic Clostridium difficile isolates compared with toxigenic culture

^*Sensitivity, specificity, PPV, and NPV are calculated as follows (×100): sensitivity, (number of true-positive assay results)/(sum of toxigenic culture-positive results); specificity, (number of true-negative assay results)/(sum of toxigenic culture-negative results); PPV, (number of true-positive assay results)/(sum of true-positive and false-positive assay results); NPV, (number of true-negative assay results)/(sum of true-negative and false-negative assay results).

Abbreviations: Xpert CD, Xpert Clostridium difficile assay; VIDAS-CDAB, VIDAS Clostridium difficile A & B assay; PPV, positive predictive value; NPV, negative predictive value.