Table 3 The results of subgroup analysis

Gait

 Gait speed

Alone tDCS

7

0.249

− 0.164

0.660

0.449

Combined tDCS

6

0.231

− 0.112

0.574

0.187

 Stride length

Alone tDCS

5

0.325

− 0.223

0.873

0.246

Combined tDCS

5

0.315

− 0.106

0.736

0.143

 Cadence

Alone tDCS

5

− 0.570

− 1.075

− 0.066

0.027*

Combined tDCS

5

− 0.666

− 1.039

− 0.294

 < 0.001**

 FOG− Q

Alone tDCS

2

− 0.375

− 0.815

0.064

0.094

Combined tDCS

2

− 0.338

− 0.847

0.17

0.192

 Step length

Alone tDCS

–

–

–

–

–

Combined tDCS

3

0.459

− 0.031

0.949

0.066

 Walking time

Alone tDCS

3

− 0.253

− 0.758

0.252

0.327

Combined tDCS

–

–

–

–

–

 Stride time

Alone tDCS

3

− 1.262

− 2.073

− 0.450

0.002**

Combined tDCS

1

− 0.347

− 1.068

0.374

0.345

 Double support time

Alone tDCS

–

–

–

–

–

Combined tDCS

3

1.139

− 0.244

2.523

0.107

Balance

 TUG

Alone tDCS

12

− 0.335

− 0.624

− 0.045

0.023*

Combined tDCS

8

− 0.237

− 0.582

0.108

0.178

 BBS

Alone tDCS

1

0.144

− 0.529

0.817

0.675

Combined tDCS

2

0.621

0.014

1.227

0.045*

 DGI

Alone tDCS

1

0.292

− 0.665

1.249

0.550

Combined tDCS

1

0.262

− 0.349

1.084

0.552