Table 1

Sensitivity, specificity and predictive values of dacron or nylon-flocked SCVS and FCU using analyte-specific reagents in a transcription-mediated amplification assay

Study groupSample% Sensitivity% Specificity% PPV% NPV
Group A (n=241)Dacron SCVS97.2 (35/36)*97.6 (200/205)87.5 (35/40)99.5 (200/201)
FCU41.7 (15/36)100 (205/205)100 (15/15)90.7 (205/226)
Group B (n=289)Dacron SCVS92.3 (36/39)98.8 (247/250)92.3 (36/39)98.8 (247/250)
Nylon-flocked SCVS92.3 (36/39)99.2 (248/250)94.7 (36/38)98.8 (248/251)
  • SCVS versus FCU in group A p<0.001.

  • * A total of 36 true positives determined by both analyte-specific reagent results positive in SCVS and FCU, or a single analyte-specific reagent positive confirmed by an alternative RUO assay.

  • The reference standard for comparison was set as positive in both swab types or single positives that were confirmed by RUO reagents.

  • FCU, first-catch urine; NPV, negative predictive value; PPV, positive predictive value; RUO, research use only; SCVS, self-collected vaginal swabs.