TABLE 4.

Sensitivity, specificity, PPV, and NPV values for IS6110 RFLP and MIRU-VNTR genotyping methods based on correct identification of an independently genotyped drug-resistant cluster characterized by unique mutations in the katG, rpoB, embB, and rrs genes

MethodValue (95% CI) when GD = 0fValue (95% CI) when= 1f
SensitivitySpecificityPPVNPVSensitivitySpecificityPPVNPV
IS6110 RFLP0.83 (0.66-0.93)1.00 (0.48-1.00)1.00 (0.88-1.00)0.45 (0.17-0.77)0.94 (0.81-0.99)1.00 (0.48-1.00)1.00 (0.89-1.00)0.71 (0.29-0.96)
MIRU-VNTR locus combinations
    12-MIRUa1.00 (0.90-1.00)0.20 (0.01-0.72)0.90 (0.76-0.97)1.00 (0.03-1.00)1.00 (0.72-1.00)0.00 (0.00-0.54)0.88 (0.72-0.95)ND
    12-MIRU + ETR A, B, Cb0.97 (0.85-1.00)0.20 (0.01-0.72)0.89 (0.75-0.97)0.50 (0.01-0.99)1.00 (0.72-1.00)0.00 (0.00-0.54)0.88 (0.72-0.95)ND
    12-MIRU + hypervariable locic0.80 (0.63-0.92)0.20 (0.01-0.72)0.88 (0.71-0.96)0.13 (0.00-0.53)0.97 (0.85-1.00)0.00 (0.00-0.52)0.87 (0.73-0.96)0.00 (0.00-0.98)
    15-MIRU-VNTRd0.91 (0.77-0.98)0.40 (0.05-0.85)0.91 (0.77-0.98)0.40 (0.05-0.85)1.00 (0.72-1.00)0.00 (0.00-0.537)0.88 (0.72-0.95)ND
    15-MIRU-VNTR + hypervariable locie0.74 (0.57-0.88)0.40 (0.05-0.85)0.90 (0.73-0.98)0.18 (0.02-0.52)0.94 (0.81-0.99)0.00 (0.00-0.52)0.87 (0.72-0.96)0.00 (0.00-0.84)
    24-MIRU-VNTRd0.91 (0.77-0.98)0.40 (0.05-0.85)0.91 (0.77-0.98)0.40 (0.05-0.85)1.00 (0.72-1.00)0.00 (0.00-0.54)0.88 (0.72-0.95)ND
    24-MIRU-VNTR + hypervariable locic0.74 (0.57-0.88)0.40 (0.05-0.85)0.90 (0.73-0.98)0.18 (0.02-0.52)0.74 (0.57-0.88)0.40 (0.05-0.85)0.90 (0.73-0.98)0.18 (0.02-0.52)
  • a According to reference 22.

  • b According to reference 8.

  • c According to this study.

  • d According to reference 21.

  • e According to reference 10.

  • f Abbreviations: ND, not determined; PPV, positive predictive value; NPV, negative predictive value; CI, confidence interval; GD, genetic distance.