Table 2.

Blinding data from Vernon et al. (2013) and Sample size/Power

a. Blinding data
	Guess			Total
Allocation	Real	Sham	Don’t know	Sample size
Real	16	9	7	32
Sham	9	15	8	32

b. Sample size and power ( $\alpha =0.05$)
N	Power of Pearson Chi-square	Power of LR
20	0.14	0.14
50	0.30	0.30
100	0.56	0.55
176	0.80	0.81
200	0.85	0.86
300	0.96	0.96