Table 4.

Meta-analysis results.

Group	Effect size (Difference in means)	Confidence interval		p value	$I^2$
		Upper limit	Lower limit
$\alpha$	−0.727	−0.573	−0.881	< 0.001	99.994
$\beta$	0.123	0.288	−0.043	0.146	99.995
$\theta$	−1.739	−1.289	−2.188	< 0.001	99.993
$\delta$	−0.046	0.019	−0.112	0.167	99.413
SNR	0.462	0.512	0.412	< 0.001	99.828
SSVEP amplitude	0.144	0.225	0.064	< 0.001	99.901
$\frac{\alpha +\theta }{\beta }$	−0.336	−0.267	−0.404	< 0.001	98.787