Comparison 3. Planned subgroup analysis by location of stimulation (lesioned or non‐lesioned hemisphere) and type of stimulation (A‐tDCS, C‐tDCS, S‐tDCS).

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Functional communication at the end of intervention phase	3		Std. Mean Difference (IV, Random, 95% CI)	Subtotals only
1.1 A‐tDCS over lesioned hemisphere	2	84	Std. Mean Difference (IV, Random, 95% CI)	0.20 [‐0.24, 0.63]
1.2 Dual‐tDCS over both hemispheres	1	28	Std. Mean Difference (IV, Random, 95% CI)	0.10 [‐0.67, 0.87]