TABLE 3

Optimal opa CT cutoff value and performance of the real-time PCR for Neisseria gonorrhoeae identification compared to that of commercial NAATsa

Sample siteopa cutoffNo. of isolates with the following result:Sensitivity (95% CI)bSpecificity (95% CI)b
TPFPFNTNTotal
Urethra26.143031311770.93 (0.82, 0.99)1.00 (0.97, 1.00)
Rectum33.746122701300.96 (0.86, 0.99)0.85 (0.76, 0.92)
Pharynx31.35396901580.90 (0.79, 0.96)0.91 (0.83, 0.96)
Cervix28.44007111.00 (0.4, 1.00)1.00 (0.59, 1.00)
Vagina33.43109131.00 (0.29, 1.00)0.90 (0.55, 1.00)
All sites combined3314922113074890.92 (0.87, 0.96)0.91 (0.87, 0.94)
  • a CI, confidence interval; TP, true positive; FP, false positive; FN, false negative; TN, true negative.

  • b Sensitivity and specificity were calculated using the results of the commercial NAATs as the reference standard.