TABLE 1.

Comparison of HC2 CT-ID and GC-ID test algorithm performance to culture and DFA and PCR adjudicated results

Site, test, and comparison% Sensitivity95% CIe% Specificity% PPVf% NPVf
1 (Birmingham)a
CT-ID
HC2 vs. culture97.6 (40/41)0.871-0.99997.5 (425/436)78.4 (40/51)99.8 (425/426)
HC2 vs. adjudicated98.0 (48/49)0.892-0.99999.3 (425/428)94.1 (48/51)99.8 (425/426)
Culture vs. adjudicated83.7 (41/49)0.703-0.927100 (428/428)100 (41/41)98.2 (428/436)
GC-ID
HC2 vs. culture90.0 (54/60)0.795-0.96298.1 (409/417)87.1 (54/62)98.6 (409/415)
HC2 vs. adjudicated91.0 (61/67)0.815-0.96699.8 (409/410)98.4 (61/62)98.6 (409/415)
Culture vs. adjudicated89.6 (60/67)0.797-0.957100 (410/410)100 (60/60)98.3 (410/417)
2 (Baltimore)b
CT-ID
HC2 vs. culture94.1 (16/17)0.713-0.99995.4 (167/175)66.7 (16/24)99.4 (167/168)
HC2 vs. adjudicated95.7 (22/23)0.781-0.99998.8 (167/169)91.7 (22/24)99.4 (167/168)
Culture vs. adjudicated73.9 (17/23)0.516-0.898100 (169/169)100 (17/17)96.6 (169/175)
GC-ID
HC2 vs. culture91.7 (11/12)0.615-0.99893.9 (169/180)50.0 (11/22)99.4 (169/170)
HC2 vs. adjudicated95.7 (22/23)0.781-0.999100 (169/169)100 (22/22)99.4 (169/170)
Culture vs. adjudicated52.2 (12/23)0.306-0.732100 (169/169)100 (12/12)93.9 (169/180)
Combined
CT-ID
HC2 vs. culturec96.6 (56/58)0.881-0.99696.9 (592/611)74.7 (56/75)99.7 (592/594)
HC2 vs. adjudicated97.2 (70/72)0.903-0.99799.2 (592/597)93.3 (70/75)99.7 (592/594)
Culture vs. adjudicated80.6 (58/72)0.695-0.889100 (597/597)100 (58/58)97.7 (597/611)
GC-ID
HC2 vs. cultured90.3 (65/72)0.810-0.96096.8 (578/597)77.4 (65/84)98.8 (578/585)
HC2 vs. adjudicated92.2 (83/90)0.846-0.96899.8 (578/579)98.8 (83/84)98.8 (578/585)
Culture vs. adjudicated80.0 (72/90)0.703-0.877100 (579/579)100 (72/72)97.0 (579/597)
  • a A total of 252 specimens were examined by both the CT-ID and GC-ID tests. The data analyses were based on the algorithm results and 477 specimens tested by the CT/GC kit.

  • b A total of 115 clinical specimens were tested by both CT-ID and GC-ID kits for this site, and 192 specimens were tested by the CT/GC kit.

  • c McNemar's two-sided P value is 0.0005.

  • d McNemar's two-sided P value is 0.0310.

  • e Confidence intervals (CI) were calculated by the binomial method.

  • f PPV, positive predictive value; NPV, negative predictive value.