Table 2.
Demographic characteristics of the study sample (n = 35)
| Smile | Waitlist | ||
|---|---|---|---|
| Characteristic | n = 23 | n = 12 | |
| Age, mean (SD), years | 23.5 (4.9) | 21.4 (1.4) | t(33) = -1.44, p = .06 |
| Gender, n (%) | |||
| Female | 19 (82.6) | 7 (58.3) | |
| Male | 4 (17.4) | 5 (41.7) | Χ² (1) = 2.43, p = .12 |
| Nationality, n (%) | |||
| Dutch | 8 (34.8) | 7 (58.3) | |
| Other | 15 (65.2) | 5 (41.7) | Χ² (1) = 1.79, p = .28 |
| Relationship status, n (%) | |||
| In a relationship | 6 (26.1) | 5 (41.7) | |
| Married or cohabitating | 2 (8.7) | - | |
| Single | 15 (65.2) | 7 (58.3) | Χ² (2) = 1.71, p = .43 |
| Medication, n (%) | |||
| No medication | 19 (82.6) | 11 (91.7) | |
| Antidepressants | 1 (4.3) | - | |
| Non-psychoactive medication | 1 (4.3) | 1 (8.3) | |
| Iron supplements | 2 (8.7) | - | Χ² (3) = 1.86, p = .60 |
| Alcohol use, n (%) | |||
| Yes | 18 (78.3) | 7 (58.3) | Χ² (1) = 0.22, p = .26 |
| No | 5 (21.8) | 5 (41.7) | |
| Insomnia Severity (ISI), mean (SD) | 14.3 (3.1) | 15.7 (5.4) | t(33) = 0.98, p = .12 |
| Depressive symptoms (BDI II), mean (SD) | 11.9 (7.1) | 11.5 (6.0) | t(33) = -0.15, p = .67 |
| Anxiety symptoms (HADS-A), mean (SD) | 8.9 (3.3) | 8.8 (4.7) | t(33) = -0.06, p = .50 |
| Quality of Life (Q-LES-Q), mean (SD) | 54.7 (13.6) | 61.2 (10.1) | t(33) = 1.45, p = .37 |
| Pre-Sleep Arousal (PSAS), mean (SD) | 42.6 (8.8) | 42.1 (10.6) | t(33) = -0.16, p = .41 |
| Dysfunctional Beliefs and Attitudes about Sleep (DBAS), mean (SD) | 73.2 (19.8) | 78.4 (20.8) | t(33) = -0.47, p = .97 |
Note. Non-psychoactive medication: Ibuprofen n = 1; Antibiotics n = 1