TABLE 4.

Intralaboratory reproducibility of DST methods using a CC of 0.25 μg/ml for the agar proportion method, a BDQ breakpoint of 0.12 μg/ml for the BMD method, and a CC of 1 μg/ml for the MGIT960 method

Laboratory	DST methoda	n	% of M. tuberculosis isolates with reproducible results
			All	Wild type	Rv0678	atpE
Lab-1	Agar proportion	39	100.0	100.0	100.0	100.0
	BMD frozen	39	100.0	100.0	100.0	100.0
	BMD dry	40	100.0	100.0	100.0	100.0
	MGIT960	40	97.5	96.7	100.0	100.0
Lab-2	Agar proportion	40	100.0	100.0	100.0	100.0
	BMD frozen	40	100.0	100.0	100.0	100.0
	BMD dry	40	100.0	100.0	100.0	100.0
	MGIT960	40	100.0	100.0	100.0	100.0
Lab-3	Agar proportion	40	97.5	96.7	100.0	100.0
	BMD frozen	40	87.5	83.3	100.0	100.0
	BMD dry	40	95.0	93.3	100.0	100.0
	MGIT960	40	100.0	100.0	100.0	100.0
Lab-4	Agar proportion	40	97.5	100.0	87.5	100.0
	BMD frozen	38	94.7	100.0	71.4	100.0
	BMD dry	38	100.0	100.0	100.0	100.0
	MGIT960	40	100.0	100.0	100.0	100.0
Lab-5	Agar proportion	32	90.6	100.0	62.5	100.0
	BMD frozen	24	83.3	85.7	66.7	—b
	BMD dry	37	97.3	96.3	100.0	100.0
	MGIT960	39	100.0	100.0	100.0	100.0

^aBMD, broth microdilution; DST, drug susceptibility testing; MGIT, Mycobacteria Growth Indicator Tube.

^b—, no valid reproducibility result for Lab-5.