TABLE 1.

Results of phase I generated by the six study sites in AST of 10 susceptible strains of M. tuberculosis

Antimicrobial agent	BACTEC 460 medium		Middlebrook 7H10 agar
	Inhibitory concn (μg/ml)	Count (%)a	Inhibitory concn (μg/ml)	Count (%)
Capreomycin	≤1.25	59 (98.3)	10.0	59 (98.3)
	2.5	1 (1.7)
Cycloserine	≤50	27 (45)	25.0	36 (60)
	60.0	23 (38.3)
	70.0	9 (15)
	>70.0	1 (1)
Ethionamide	≤1.25	59 (98.3)	5.0	59 (98.3)
	2.5	1 (1.7)
Kanamycin	≤1.25	48 (80)	5.0	60 (100)
	2.5	12 (20)
Amikacin	≤1.0	60 (100)	≤2.0	54 (90)
			>4.0	6 (10)
Clofazimine	≤0.25	59 (98.3)	≤0.25	47 (78.3)
	0.5	1 (1.7)	0.5	13 (21.7)
Ciprofloxacin	≤0.5	46 (76.7)	≤0.5	41 (68.3)
	1.0	13 (21.7)	1.0	18 (30)
	2.0	1 (1.7)	2.0	1 (1.7)
Ofloxacin	≤0.5	21 (35)	≤0.5	19 (31.7)
	1.0	34 (56.7)	1.0	38 (63.3)
	2.0	4 (6.7)	2.0	3 (5)
	>4.0	1 (1.7)

^aThe count is the total number of susceptible strains.