Students’ demographic data, sleep quality and academic expectations stress
According to the independent sample t test analysis, female students' sleep quality scores and stress scores (X̄ = 6.70, SD = 3.37; X̄ = 31.75, SD = 8.65) were compared to male students (x̄ = 6.19, SD = 3.18; X̄ = 29.66, SD = 8.79) was statistically significant (t (1159) = 2.664, p < 0.01, d = 0.16; t (1159) = 2.664, p < 0.01, d = 0.24. Sleep quality scores of students with an existing disease (X̄ = 7.30, SD = 3.40) were higher than students without the disease (x̄ = 6.30, SD = 3.24), t (1159) = 3.654, p < 0.01, d = 0.30. No statistically significant difference was found between students with an existing disease (X̄ = 31.75, SD = 8.60) and students without disease (x̄ = 30.54, SD = 8.80), t (1159) = 1.640, p > 0.05, d = 0.14) (Table 1).
Table 1
Comparison of students' sleep quality and academic stress averages according to some demographic variables
Demographic variables | Sleep Quality X̄± SD | Test | Academic Stress X̄± SD | Test |
Total (n = 1161) | 6.47 ± 3.30 | | 30.71 ± 8.78 | |
Male (n = 576) | 6.19 ± 3.18 | t = 2.664* df = 1159 d = 0.16 | 29.66 ± 8.79 | t = 4.067* df = 1159 d = 0.24 |
Female (n = 585) | 6.70 ± 3.37 | 31.75 ± 8.65 |
Those who do not have a disease (n = 996) | 6.30 ± 3.24 | t = 3.654* df = 1159 d = 0.30 | 30.54 ± 8.80 | t = 1.640 df = 1159 d = 0.14 |
Those with the disease (n = 165) | 7.30 ± 3.40 | 31.75 ± 8.60 |
The nuclear family (n = 932) | 6.43 ± 3.26 | F = 0.935 df = 1157 η2 = 0.002 | 30.76 ± 8.69 | F = 1.389 df = 1157 η2 = 0.002 |
Extended family (n = 173) | 6.32 ± 3.39 | 29.96 ± 8.78 |
Single parent family (n = 56) | 7.00 ± 3.24 | 32.14 ± 10.06 |
Bad economic situation (n = 18)a | 7.33 ± 3.22 | F = 4.575* df = 1157 η2 = 0.011 b > c | 29.39 ± 10.52 | F = 0.355 df = 115 η2 = 0.001 |
Normal economic situation (n = 472) b | 6.80 ± 3.33 | 30.49 ± 8.53 |
Good economic situation (n = 588)c | 6.23 ± 3.17 | 30.91 ± 8.83 |
Very good economic situation (n = 83)d | 5.72 ± 3.60 | 30.90 ± 9.42 |
Having their room (n = 838) | 6.57 ± 3.35 | t = 2.225** df = 1159 d = 0.15 | 31.12 ± 8.57 | t = 2,540** df = 1159 d = 0.1 |
Those who do not have their own room (n = 323) | 6.09 ± 3.07 | 29.66 ± 9.24 |
*p < 0.01, **p < 0.05, F: One Way Anova, t: Independent Sample t-test, η2: Eta Square, d: Cohen’s d, x̄: Mean, SD: Standard Deviation |
Stress scores regarding sleep quality and academic expectations of students who have their own rooms (x̄=6.57, SD = 3.35; X̄=31.12, SD = 8.57) were higher than those who do not have their own rooms (X̄=6.09, SD = 3.07; X̄=29.66, SD = 9.24), t (1159) = 2.225, p < 0.05, d = 0.15; t (1159) = 2.540, p < 0.01, d = 0.16.
According to the one-way variance test result, it was determined that family type did not affect sleep quality and academic expectations stress, p > 0.05. While the economic level of the family was not effective on academic stress (p > 0.05), it was determined that it was effective on the sleep quality score, F (3,1157) = 4,575, p < 0.01, η2 = 0.011. According to the post hoc analysis performed with the Sheffie test, the PSQI score of the students who stated normal economic status (X̄ = 6.81, SD = 3.33) was significantly higher than the score of the students with good economic status (X̄ = 6.23, SD = 3.17), p < 0.05 (Table 1).
Sleep habits and academic expectations stress between middle and high school adolescents
Among high school students, the rate of experiencing poor sleep quality (68.6%) and academic expectations stress (78.2%) were higher than middle school students (respectively, 47.3%, 63.4). (Fig. 1)
Independent group t-test results related to the comparison of PSQI total score and AESI total scores and sub-dimension scores of adolescents according to their school level are given in Table 2. According to the analysis result, the sleep quality scores of the students attending high school (X̄=7.27, SD = 3.15) were significantly higher than the students who continue to middle school (X̄=5.69, SD = 3.22), (t (1159) = 8.411, p < 0.01, d = 0.49). Sub-dimensions of subjective sleep quality, sleep latency, sleep duration and daytime function of high school students (X̄=1.38, SD = 0.82; X̄=1.17, SD = 0.89; X̄=0.77, SD = 0.83, X̄=1.33, SD = 0.94) were significantly higher than middle school students' scores (X̄=0.90, SD = 0.76; X̄=1.06, SD = 0.85; X̄=0.34, SD = 0.67, X̄=0.83, SD = 0.83), p < 0.01. No statistically significant difference was found between the groups in the subscales of habitual sleep efficiency, sleep disturbance and use of sleeping pills, p > 0.05. It was determined that the AESI general score averages of the high school students (X̄=32.13, SD = 7.77) were significantly higher than the middle school students (X̄=29.42, SD = 9.43), t (1159) = 5.358, p < 0.01, d = 0.31. There was no statistically significant difference between the groups in the sub-dimensions of expectations of parents/teachers (AESI-EPT), p > 0.05. In the sub-dimension of expectations of self (AESI-ES), it was observed that the scores of the students attending high school (X̄=14.61, SD = 3.89), were significantly higher than the students who attended middle school (x̄= 12.36, SD = 4.61), t (1159) = 8.993, p < 0.01, d=0.53.
Table 2
Comparison of PSQI and AESI to the school level of adolescents
PSQI | Middle school X̄± SD (n = 607) | High school X̄± SD (n = 554) | t-value (Cohen’s d) |
Global PSQI Score | 5.69 ± 3.22 | 7.27 ± 3.15 | t = 8.411* df = 1159 d = 0.49 |
Subjective sleep quality | 0.90 ± 0.76 | 1.38 ± 0.82 | t = 10.210* df = 1159 d = 0.60 |
Sleep latency | 1.06 ± 0.85 | 1.17 ± 0.89 | t = 2.125* df = 1159 d = 0.12 |
Sleep duration | 0.34 ± 0.67 | 0.77 ± 0.83 | t = 9.626* df = 1159 d = 0.57 |
Habitual sleep efficiency | 0.10 ± 0.46 | 0.10 ± 0.47 | t=-0.033 df = 1159 d = 0.0 |
Sleep disturbances | 1.46 ± 0.70 | 1.51 ± 0.64 | t = 1.166 df = 1159 d = 0.07 |
Use of sleeping medication | 1.0 ± 1.07 | 1.01 ± 0.96 | t = 0.119 df = 1159 d = 0.0 |
Daytime dysfunction | 0.83 ± 0.83 | 1.33 ± 0.94 | t = 9.731* df = 1159 d = 0.56 |
AESI Total | 29.42 ± 9.43 | 32.13 ± 7.77 | t = 5.358* df = 1159 d = 0.31 |
AESI-EPT | 17.06 ± 5.65 | 17.52 ± 4.98 | t = 1.482 df = 1159 d = 0.08 |
AESI-ES | 12.36 ± 4.61 | 14.61 ± 3.89 | t = 8.993* df = 1159 d = 0.53 |
*p < 0.01, x̄:Mean, SD:Standard Deviation, t:Independent Sample t test, d: Cohen’s d |
Variables associated with the sleep quality of adolescents
The results of multiple linear regression analysis regarding the prediction of sleep quality of adolescents are given in Table 3. Before the model was established in the regression model, the necessary components were checked and shown in Table 3. The AESI score showed a significant relationship with the sleep quality together with the age variable, R² =0.137, F (2,1158) = 90.532, p < 0.01. The AESI score explains 13.7% of the change in sleep quality scores with age.
Table 3
Multiple regression analysis for predicting sleep quality of adolescents
Variable | B | SE B | β | t | p | Binary r | Partial r |
Constant | -1.788 | 0.642 | | -2.784 | 0.005 | | |
AESI | 0.086 | 0.010 | 0.229 | 8.317 | 0.001 | 0.24 | 0.23 |
Age | 0.390 | 0.041 | 0.260 | 9.443 | 0.001 | 0.27 | 0.26 |
Sleep quality (Dependent variable) Constant R2 = 0.137, F (2,1158) = 90.532, p < 0.01, DW = 1.812, Tolerance = 0.984, VIF = 1.016 |
DW = Durbin-Watson, R2 = R Square, VIF = Variance inflation factors |