Table. 3—

Sensitivity, specificity and positive predictive values of commonly used tests for the diagnosis of tuberculosis (TB) disease

TestChest radiographyMicrobiologicalAmplificationImmunological
SmearSingle cultureThree culturesPCRTSTSerologyCell-mediated immunity test
Sensitivity % [ref.]
 Pulmonary TB overall59–82 35, 40, 42–4450–80 28, 4680–85 28, 4680–100 28, 4650–95 49–5253–90 5321–90 5453–77 55, 56
 Smear positive80 35, 40, 42–44100 28, 4685–96 28, 4690–100 28, 4695 49–5153–73 57, 5845–96 52, 59–61
 Smear negative60 35, 40, 42–44050 28, 4680 28, 4648–53 49–5290 5216–97 52, 59–61
Specificity % [ref.]52–99 35, 40, 42–4495 28, 4698 4798 4798 49–525 5380–100 5464–100 55, 56
Positive predictive value# %2.911.629.331.326.9<15.23.5
  • TST: tuberculin skin test. #: calculated for 1% prevalence of active TB, using the mid-point of the range of sensitivity and specificity for each test; : the specificity of positive TST is to distinguish active TB disease from latent TB infection.