Table 3.

Prevalence levels of pyrazinamide resistance in culture isolates of M. tuberculosis for attaining different predictive values^a

Assay category	Critical prevalence level (%) required to attain:
	PPV of:				NPV of:
	≥85%	≥90%	≥95%	≥99%	≥85%	≥90%	≥95%	≥99%
PCR-DNA sequencing targeted at pncA mutations	≥29	≥39	≥58	≥88	≤67	≤56	≤38	≤10
Other molecular assays targeting pncA mutationsb	≥17	≥25	≥41	≥78	≤90	≤85	≤73	≤34
Wayne assay	≥17	≥25	≥41	≥78	≤66	≤55	≤36	≤10

^aBased on estimates of sensitivity and specificity obtained in the final meta-analysis. CI, confidence interval; DOR, diagnostic odds ratio; LR, likelihood ratio; NPV, negative predictive values; PPV, positive predictive value.

^bComprises line probe assay, microarray, branch migration inhibition, and denaturing gradient gel electrophoresis.