TABLE 3.

Results of PZA susceptibility testing for identification of M. bovis

ParameterTest resultb95% CIa
Any PZA resistance
    Sensitivity100 (11/11)71.5-100
    Specificity98.7 (1,496/1,515)98.0-99.2
    Positive predictive value36.7 (11/30)19.9-56.2
    Negative predictive value100 (1,496/1,496)99.8-100
PZA monoresistance
    Sensitivity81.8 (9/11)48.2-97.7
    Specificity99.4 (1,506/1,515)98.9-99.7
    Positive predictive value50.0 (9/18)26.0-74.0
    Negative predictive value99.9 (1,506/1,508)99.5-100
  • a CI, confidence interval.

  • b Values are percentages. Values in parentheses were used to calculate the percentages and were obtained as follows: sensitivity, a/(a + c); specificity, d/(b + d); positive predictive value, a/(a+ b); and negative predictive value, d/(c + d). In these calculations, a is the number of M. bovis isolates that were PZA (mono)resistant, b is the number of M. tuberculosis isolates that were PZA (mono)resistant, c is the number of M. bovis isolates that were PZA susceptible, and d is the number of M. tuberculosis isolates that were PZA susceptible.