Table 3.

Sensitivity, specificity, and predictive values of the PCR/ESI-MS Mycobacterium assay for identification and species identification of 264 mycobacterial isolates directly from AFB-positive MGIT broth culture media^a

Mycobacterial species, complex, or group, according to PCR/ESI-MS	No. of isolates with indicated PCR/ESI-MS result				Sensitivity (%)	Specificity (%)	PPV (%)	NPV (%)
	Correct positive	Incorrect positive	Incorrect negative	Correct negative
M. tuberculosis complex	49	1	0	218	98.0	100.0	100.0	99.5
M. avium/M. intracellulare	157	0	1	106	100.0	99.1	99.4	100.0
M. chelonae/M. abscessus group	15	2	0	249	88.2	100.0	100.0	99.2
M. fortuitum group	7	0	0	259	100.0	100.0	100.0	100.0
M. gordonae	10	2	0	256	83.3	100.0	100.0	99.2
M. kansasii	16	3	0	249	84.2	100.0	100.0	98.8
M. simiae	1	0	0	267	100.0	100.0	100.0	100.0
M. szulgai	3	0	0	265	100.0	100.0	100.0	100.0
Total	258	8	1	1869	97.0	99.9	99.6	99.6

^aPPV, positive predictive value; NPV, negative predictive value.