Sleep schedules and sleep-related problems | Total | High ADHD symptoms [n (%)] | χ 2 | P |
---|---|---|---|---|
Bedtime on weekday | ||||
 Before 9:00 PM | 5828 | 417 (7.2) | 90.54 | < 0.001 |
 Between 9:00 and 10:00 PM | 8032 | 685 (8.5) |  |  |
 After 10:00 PM | 1431 | 215 (15.0) |  |  |
Bedtime on weekend | ||||
 Before 9:00 PM | 3673 | 256 (7.0) | 53.49 | < 0.001 |
 Between 9:00 and 10:00 PM | 8300 | 675 (8.1) |  |  |
 After 10:00 PM | 3318 | 386 (11.6) |  |  |
Waking time on weekday | ||||
 Before 6:00 AM | 629 | 61 (9.7) | 1.66 | 0.437 |
 Between 6:00 and 8:00 AM | 14,249 | 1216 (8.5) |  |  |
 After 8:00 AM | 413 | 40 (9.7) |  |  |
Waking time on weekend | ||||
 Before 6:00 AM | 361 | 39 (10.8) | 9.85 | 0.007 |
 Between 6:00 and 8:00 AM | 9640 | 780 (8.1) |  |  |
 After 8:00 AM | 5290 | 498 (9.4) |  |  |
Time falling asleep | ||||
  ≤ 15 min | 2813 | 187 (6.6) | 70.31 | < 0.001 |
 16~ 30 min | 8561 | 669 (7.8) |  |  |
  ≥ 31 min | 3917 | 461 (11.8) |  |  |
Sleep duration | ||||
  ≤ 8.5 h | 4570 | 467 (10.2) | 21.36 | < 0.001 |
 8.6~ 9.4 h | 6458 | 512 (7.9) |  |  |
  ≥ 9.5 h | 4263 | 338 (7.9) |  |  |
Having naps | ||||
 Often | 9437 | 728 (7.7) | 33.19 | < 0.001 |
 Occasionally | 3737 | 347 (9.3) |  |  |
 No | 2117 | 242 (11.4) |  |  |
Having sleep-related problems | ||||
 Often | 4017 | 639 (15.9) | 408.79 | < 0.001 |
 Occasionally | 6508 | 485 (7.5) |  |  |
 No | 4766 | 193 (4.0) |  |  |