Table 2.

Power under a range of sample sizes and filtration scenarios. Here power is defined as the proportion of replicates out of ten in which the erm gene was found to be associated with erythromycin resistance. Scenario 1: following Fisher’s exact test; Scenario 2: same as 1 but added population size correction (p value range < 0.05); Scenario 3: Same as 2 but with additional requirement that the empirical p values after 1000 permutations were < 0.05

Sample size (N)	Scenario 1	Scenario 2	Scenario 3
20	0.2	0.0	0.0
50	1.0	0.0	0.0
80	1.0	0.2	0.2
110	1.0	0.8	0.4
140	1.0	0.8	0.7
170	1.0	1.0	0.6
200	1.0	0.9	0.8