Table 2.

The stimulation parameters in the included studies.

References	Stimulation settings (mean ±SD)
	Voltage (V)	Pulse width (μS)	Frequency (Hz)
Baldermann et al. (2018)	2.62 ± 0.86	102.00 ± 25.29	15.50 ± 7.61
Leoutsakos et al. (2018)	NM	NM	NM
Mao et al. (2018)	1 to 5	90.00	130.00
Sankar et al. (2015)	3.0 to 3.5	90.00	130.00
Scharre et al. (2018)	NM	NM	NM

SD, standard deviation; NM, not mentioned.