Table 2

Power with 24 randomisation units for various Intra-class correlations coefficient in all countries, with alpha=0.05

Variance of the random effect	Approximate intraclass correlation coefficients	Difference in the change from phase 1 to phase 2 in the number of household contact starting latent tuberculosis infection treatment per index tuberculosis patient between the intervention and control arms	Power (%)
0.7	0.21	5	28
1.4	0.30	5	32
2.8	0.40	5	26
0.7	0.18	10	74
1.4	0.28	10	76
2.8	0.38	10	73
0.7	0.18	15	96
1.4	0.26	15	97
2.8	0.36	15	97
0.7	0.16	30	100
1.4	0.22	30	100
2.8	0.31	30	100