TABLE 3.

Daytime Sleepiness, Sleep Problem Behavior, Depressive Mood, and Morningness/Eveningness Scales by Grade (Mean ± SD)

ScalesGradeF Values
5–6 (A) (N = 525)7–8 (B) (N =343)9–10 (C) (N = 251)11–12 (D) (N = 338)GenderGradePost-hoc
Daytime sleepiness14.2 ± 3.715.5 ± 3.818.4 ± 4.619.0 ± 4.210.75*120.16A < B < C = D
    Boys14.0 ± 3.815.0 ± 3.917.7 ± 4.818.8 ± 4.3Grade × Gender (F = 0.72, P = .5373)
    Girls14.3 ± 3.616.0 ± 3.718.8 ± 4.419.2 ± 3.8
Sleep-problems behavior 17.6 ± 6.419.7 ± 6.323.4 ± 6.323.5 ± 5.54.0481.72A < B < C = D
    Boys17.0 ± 6.519.7 ± 6.323.4 ± 6.323.6 ± 5.8Grade × Gender (F = 1.11, P = .3435)
    Girls18.1 ± 6.220.3 ± 6.223.7 ± 6.023.3 ± 5.1
Depressive mood8.1 ± 2.59.1 ± 2.710.2 ± 3.019.7 ± 2.729.1584.97A < B < C = D
    Boys7.9 ± 2.58.8 ± 2.89.8 ± 2.910.1 ± 2.6Grade × Gender (F = 4.59, P = .0033)
    Girls8.2 ± 2.49.5 ± 2.610.5 ± 3.111.8 ± 2.7
Morningness/eveningness29.1 ± 4.827.6 ± 4.324.8 ± 4.125.0 ± 4.111.82§80.05A > B > C = D
    Boys29.4 ± 4.928.5 ± 4.625.4 ± 4.325.0 ± 4.1Grade × Gender (F = 3.16, P = .0237)
    Girls28.8 ± 4.726.6 ± 3.724.5 ± 3.925.0 ± 3.9
  • * P < .01.

  • P < .0001.

  • P < .05.

  • § P < .001.

  • The higher the score, the more morning preference.

  • The higher the score, the more the problems.