Table 1.

Results of molecular beacon assay

Drug, isolate, and susceptibilityNo. of isolatesSensitivity95% CIa for sensitivitySpecificity95% CI for specificity
TotalAssay positiveAssay negative
Isoniazid
 Total susceptible550551.000.94–1.00b
  Madrid7071.000.59–1.00b
  New York480481.000.92–1.00b
 Total resistant9480140.850.76–0.92
  Madrid494630.940.83–0.99
   MDR434120.950.84–0.99
   Single-drug resistantc6510.830.36–0.99
  New York4534110.760.61–0.87
   MDR272610.960.81–1.00b
   Single-drug resistant188100.440.22–0.69
Rifampin
 Total susceptible820821.000.96–1b
  Madrid150151.000.78–1b
  New York670671.000.95–1b
 Total resistant676610.980.93–0.99
  Madrid414010.980.87–0.99
   MDR414010.980.87–0.99
   Single-drug resistantc0
  New York262601.000.87–1.00b
   MDR262601.000.87–1.00b
   Single-drug resistant0
  • a CI, confidence interval.

  • b One-tailed 97.5% confidence interval.

  • c Ethambutol susceptibility not known.