Table 2. Frequency of Adverse Events at Least Remotely Associated With Interventiona.
| Adverse Event | Week 2 | Week 6 | ||||
|---|---|---|---|---|---|---|
| No. (%) | P Valueb | No. (%) | P Valueb | |||
| Sham (n = 26) |
Active (n = 27) |
Sham (n = 26) |
Active (n = 26) |
|||
| Headache | 12 (46) | 8 (30) | .21 | 6 (23) | 8 (31) | .53 |
| Neck pain | 1 (4) | 1 (4) | >.99 | 0 | 1 (4) | .32 |
| Discomfort, left side | 5 (19) | 7 (26) | .56 | 3 (12) | 5 (19) | >.99 |
| Discomfort, right side | 5 (19) | 7 (26) | .56 | 4 (15) | 5 (19) | >.99 |
| Tingling | 15 (58) | 15 (56) | .87 | 12 (46) | 14 (54) | .57 |
| Itching | 2 (9) | 7 (28) | .14 | 2 (8) | 8 (31) | .07 |
| Burning | 7 (30) | 11 (44) | .33 | 4 (15) | 8 (31) | .32 |
| Skin redness | 5 (19) | 11 (41) | .08 | 5 (19) | 14 (54) | .01 |
| Sleepiness | 10 (38) | 9 (33) | .69 | 9 (35) | 6 (23) | .35 |
| Trouble concentrating | 1 (4) | 1 (4) | >.99 | 0 | 1 (4) | >.99 |
| Fatigue | 1 (4) | 0 | .47 | 2 (8) | 1 (4) | >.99 |
| Nausea | 3 (13) | 2 (8) | .66 | 2 (8) | 1 (4) | >.99 |
| Dizziness | 2 (9) | 2 (8) | >.99 | 0 | 2 (8) | .49 |
| TEAS episode | NA | NA | NA | 5 (19) | 4 (15) | .71 |
Abbreviation: NA, not applicable; TEAS, treatment-emergent affective switch.
a
Adverse events were assessed using a commonly used tDCS questionnaire. At the end of weeks 2 and 6, all participants were asked to complete these questionnaires, describing the presence of an adverse event, its severity (mild, moderate, or severe), and its relationship to the treatment (1, none; 2, remote; 3, possible; 4, probable; or 5, certain).
b
P values were determined with χ2or Fisher exact test.