Prevalence (%) of symptoms of DSM-IV and DSM-5 insomnia (n=1037)
| Aged 4 years (95% CI) | Aged 6 years (95% CI) | Aged 8 years (95% CI)* | Aged 10 years (95% CI) | Aged 12 years (95% CI) | Aged 14 years (95% CI) | |
| DSM-IV insomnia | ||||||
| Initiating symptom | 7.8 (6.0 to 9.6) | 10.0 (7.8 to 12.2) | 15.5 (12.6 to 18.5) | 18.0 (15.0 to 21.1) | 15.7 (12.8 to 18.7) | 12.3 (9.5 to 15.2) |
| Maintaining symptom | 4.7 (3.3 to 6.2) | 3.1 (1.8 to 4.4) | 1.0 (0.2 to 1.8) | 1.0 (0.3 to 1.7) | 1.0 (0.2 to 1.8) | 0.8 (0.0 to 1.6) |
| Not rested symptom | 3.3 (2.1 to 4.6) | 5.7 (4.0 to 7.4) | 13.0 (10.3 to 15.7) | 6.9 (4.9 to 8.8) | 6.9 (4.7 to 9.0) | 13.3 (10.4 to 16.2) |
| At least one symptom of DSM-IV insomnia | 13.8 (11.5 to 16.1) | 15.4 (12.7 to 18.1) | 23.2 (19.8 to 26.7) | 22.0 (18.8 to 25.3) | 19.5 (16.3 to 22.8) | 20.3 (16.9 to 23.7) |
| DSM-5 insomnia | ||||||
| Initiating symptom | n/a | n/a | n/a | 22.0 (18.7 to 25.4) | 16.9 (13.8 to 20.0) | 14.4 (11.3 to 17.5) |
| Maintaining symptom | n/a | n/a | n/a | 8.3 (6.1 to 10.5) | 4.4 (2.6 to 6.2) | 1.8 (0.7 to 2.9) |
| Early awakening symptom | n/a | n/a | n/a | n/a | n/a | n/a |
| At least one symptom of DSM-5 insomnia | n/a | n/a | n/a | 27.3 (23.7 to 30.8) | 19.5 (16.2 to 22.8) | 14.7 (11.7 to 17.7) |
Ages 4–6 years, parent report; ages 8–14, joint report.
*Proxy insomnia at age 8 years—thresholds of 1-hour sleep latency/time awake at night.
DSM, Diagnostic and Statistical Manual of Mental Disorders; n/a, not available.