Table 3 Subgroup analyses of the effects of tDCS on cognitive function
Variables | Number of studies / subjects | SMD (95%CI) | I2 (%) | p-value |
|---|---|---|---|---|
Global cognition at immediate effects | ||||
 - ADAS-Cog | 4 / 223 | 0.70 (-0.31, 1.71) | 90 | 0.17 |
 - MMSE | 5 / 203 | 0.51 (0.15, 0.86) | 24 | 0.005 |
 - MoCA | 7 / 347 | 0.28 (-0.28, 0.84) | 83 | 0.32 |
Global cognition at long-term effects | ||||
 - ADAS-Cog | 3 / 272 | -0.06 (-0.30, 0.17) | 0 | 0.60 |
 - MMSE | 6 / 322 | 2.29 (1.04, 3.55) | 94 | 0.0003 |
 - MoCA | 3 / 103 | 0.10 (-0.29, 0.49) | 0 | 0.61 |
Memory function at immediate effects | ||||
 - Verbal | 5 / 277 | 0.14 (-0.10, 0.38) | 0 | 0.25 |
 - Working | 3 / 189 | -0.17 (-0.46, 0.12) | 50 | 0.24 |
Memory function at long-term effects | ||||
 - Working | 3 / 277 | -0.01 (-0.25, 0.22) | 0 | 0.92 |
Executive function at immediate effects | ||||
 - Stroop test color | 3 / 198 | 0.44 (-1.71, 2.58) | 0 | 0.69 |
 - Stroop test word | 3 / 198 | 0.03 (-5.44, 5.50) | 69 | 0.99 |
 - Stroop test color-word | 3 / 200 | 3.07 (-0.35, 6.49) | 0 | 0.08 |