Table 1.
Baseline characteristics
| Control group (n=1864) | Treatment group (n=1891) | |||
|---|---|---|---|---|
| Mean age (years) | 24·6 (7·6) | 24·8 (7·7) | ||
| Mean total UCAS points | 753·0 (517·3) | 720·8 (456·3) | ||
| Sex | ||||
| Male | 530 (28%) | 513 (27%) | ||
| Female | 1315 (71%) | 1361 (72%) | ||
| Other | 19 (1%) | 17 (1%) | ||
| Course level | ||||
| Undergraduate | 1352 (73%) | 1389 (73%) | ||
| Postgraduate | 480 (26%) | 473 (25%) | ||
| Other | 32 (2%) | 29 (2%) | ||
| Ethnic origin | ||||
| White | ||||
| British | 1212 (65%) | 1265 (67%) | ||
| Irish | 32 (2%) | 27 (1%) | ||
| Other | 284 (15%) | 261 (14%) | ||
| Mixed | ||||
| White and Caribbean | 13 (1%) | 11 (1%) | ||
| White and African | 9 (<1%) | 13 (1%) | ||
| White and Asian | 31 (2%) | 27 (1%) | ||
| Other | 36 (2%) | 29 (2%) | ||
| Asian | ||||
| Indian | 26 (1%) | 43 (2%) | ||
| Pakistani | 23 (1%) | 22 (1%) | ||
| Bangladeshi | 9 (<1%) | 7 (<1%) | ||
| Chinese | 95 (5%) | 73 (4%) | ||
| Other | 25 (1%) | 32 (2%) | ||
| Black | ||||
| African | 26 (1%) | 23 (1%) | ||
| Caribbean | 10 (1%) | 17 (1%) | ||
| Other | 2 (<1%) | 3 (<1%) | ||
| Arab | 12 (1%) | 14 (1%) | ||
| Other | 19 (1%) | 24 (1%) | ||
| Mean insomnia (SCI-8) score | 10·1 (4·3) | 9·9 (4·3) | ||
| Mean paranoia (GPTS) score | 24·8 (11·6) | 25·4 (11·9) | ||
| Mean hallucinations (SPEQ) score | 5·3 (6·9) | 5·3 (6·4) | ||
| Mean insomnia (SCI-9) score | 12·1 (4·9) | 11·9 (4·8) | ||
| Mean insomnia (ISI) score | 15·3 (4·0) | 15·4 (3·9) | ||
| Mean nightmares (DDNSI) score | 8·1 (8·2) | 7·7 (7·8) | ||
| Mean prodromal psychosis (PQ-16) score | 4·9 (3·4) | 4·8 (3·3) | ||
| Mean depression (PHQ-9) score | 12·7 (5·9) | 12·9 (5·8) | ||
| Mean anxiety (GAD-7) score | 9·0 (5·6) | 9·4 (5·6) | ||
| Mean mania (Altman) score | 3·5 (3·0) | 3·5 (3·0) | ||
| Mean functioning (WSAS) score | 17·7 (7·6) | 17·6 (7·6) | ||
| Mean wellbeing (WEMWBS) score | 37·9 (8·8) | 37·8 (8·5) | ||
| Ultra-high risk of psychosis (PQ-16) cutoff (≥6) | ||||
| Above | 706 (38%) | 711 (38%) | ||
| Below | 1158 (62%) | 1180 (62%) | ||
| Depressive disorder (PHQ-9) cutoff (≥10) | ||||
| Above | 1238 (66%) | 1286 (68%) | ||
| Below | 626 (34%) | 605 (32%) | ||
| Anxiety disorder (GAD-7) cutoff (≥10) | ||||
| Above | 781 (42%) | 880 (47%) | ||
| Below | 1083 (58%) | 1011 (53%) | ||
| Mania disorder (Altman) score cutoff (≥6) | ||||
| Above | 422 (23%) | 413 (22%) | ||
| Below | 1442 (77%) | 1478 (78%) | ||
| Contact with mental health services | ||||
| Yes | 328 (18%) | 346 (18%) | ||
| No | 1536 (82%) | 1545 (82%) | ||
| Any psychiatric diagnosis | ||||
| Yes | 590 (32%) | 641 (34%) | ||
| No | 1274 (68%) | 1250 (66%) | ||
| Previous diagnosis of a sleep disorder | ||||
| Yes | 93 (5%) | 96 (5%) | ||
| No | 1771 (95%) | 1795 (95%) | ||
| Any psychiatric medication | ||||
| Yes | 433 (23%) | 460 (24%) | ||
| No | 1431 (77%) | 1431 (76%) | ||
| Specific medication for a sleep disorder | ||||
| Yes | 51 (3%) | 55 (3%) | ||
| No | 1813 (97%) | 1836 (97%) | ||
| Psychological therapy | ||||
| Yes | 146 (8%) | 135 (7%) | ||
| No | 1718 (92%) | 1756 (93%) | ||
Data are mean (SD) or n (%). UCAS=Universities and Colleges Admissions Service. SCI-8=Sleep Condition Indicator 8-item version. GPTS=Green et al Paranoid Thought Scales. SPEQ=Specific Psychotic Experiences Questionnaire. SCI-9=SCI 9-item version. ISI=Insomnia Severity Index. DDNSI=Disturbing Dream and Nightmare Severity Index. PQ-16=Prodromal Questionnaire 16-item version. PHQ-9=Patient Health Questionnaire 9-item version. GAD-7=Generalised Anxiety Disorder 7-item version. WSAS=Work and Social Adjustment Scale. WEMWBS=Warwick–Edinburgh Mental Wellbeing Scale.