Beck Depression Inventory II scores
| Group 1 | Group 2* | |||
| Average BDI-II (SD, N) | Average reduction from BL (SD) | Average BDI-II (SD, N) | Average reduction from BL (SD) | |
| Baseline | 7.6 (6.0, 12) | n/a | 12.6 (5.0, 14) | n/a |
| Week 4 | 6.1 (5.0, 11) | 1.8 (4.4)† | 13.0 (8.2, 13) | −0.2 (7.3) |
| Week 8 (EOT) | 4.0 (4.3, 10) | 4.2 (6.5)† | 14.0 (12.6, 11) | −1.7 (9.8) |
| Month 3 | 6.1 (8.7, 10) | 1.3 (8.3)† | 15.2 (11.6, 10) | −2.4 (9.7) |
| Month 12 | 5.8 (6.0, 8) | 2.5 (6.1)† | 10.0 (16.2, 4) | 2.2 (17.8) |
*Group 2 crossed over at week 4 to receive 4 weeks of active stimulation.
†P<0.05 compared with group 2 at the end of the placebo period.
BDI-II, Beck Depression Inventory II; BL, baseline; EOT, end of treatment; n/a, not applicable.