Table 1.
Assessment of participants’ retrospective results of both light glasses (N = 23).
| Placebo | Treatment | |||||
|---|---|---|---|---|---|---|
| Mean ± SD | Number of Participants Rating [-] | Mean ± SD | Number of Participants Rating [-] | |||
| Effect on | Positive | Negative | Positive | Negative | ||
| Alertness a | 4.17 ± 0.58 | 4 | 1 | 4.83 ± 1.03 | 11 | - |
| Sleep quality a | 4.26 ± 0.62 | 4 | - | 4.48 ± 0.99 | 8 | 1 |
| Sleep length a | 4.22 ± 0.52 | 4 | - | 4.13 ± 0.87 | 5 | 3 |
| Recovery a | 4.48 ± 0.67 | 9 | - | 4.52 ± 0.99 | 9 | 1 |
| Wear b | 4.20 ± 1.15 | 4.40 ± 1.14 | ||||
| Comfort b | 3.90 ± 1.29 | 3.90 ± 1.29 | ||||
| Adverse effects | ||||||
| Headache | 6 | 4 | ||||
| Impaired vision | 3 | 5 | ||||
| Dizziness | 2 | 0 | ||||
| Concentration | 1 | 1 | ||||
a On a scale from 1–7, with 1 = much worse, 4 = no effect, 7 = much better; b On a scale from 1–7, with 1 = very unpleasant/uncomfortable, 7 = very pleasant/comfortable.