Maartje Boer

VALIDATION OF THE SMD-SCALE 47 2 Table 2.4 Logistic Regression Results, Problems Related to Mental Health, School, and Sleep, n = 6,626 Mental health problems Emotional problems 1 Conduct problems 2 Hyperactivity 3 Peer problems 4 B SE OR M% B SE OR M% B SE OR M% B SE OR M% Number of endorsed criteria 0.31*** 0.02 1.36 3.99 0.34*** 0.02 1.40 3.38 0.21*** 0.02 1.24 2.92 0.20*** 0.02 1.22 2.10 Normative SMU (max. 1 criterion) ref. (a) 10.57 ref. (a) 7.65 ref. (a) 12.77 ref. (a) 10.04 Risky SMU (2 to 5 criteria) 1.03*** (b) 0.07 2.81 24.93 1.00*** (b) 0.08 2.73 18.44 0.68*** (b) 0.06 1.98 22.51 0.49*** (b) 0.08 1.63 15.39 Problematic SMU (6 to 9 criteria) 1.74*** (c) 0.15 5.70 40.23 2.13*** (c) 0.16 8.44 41.13 1.34*** (c) 0.15 3.83 35.91 1.27*** (c) 0.16 3.56 28.43 School problems Sleep problems School dissatisfaction 5 Perceived school pressure 6 Lower sleep duration than recommended 7 Low sleep quality 8 B SE OR M% B SE OR M% B SE OR M% B SE OR M% Number of endorsed criteria 0.17*** 0.02 1.19 3.10 0.24*** 0.02 1.27 5.45 0.16*** 0.02 1.18 3.35 0.25*** 0.02 1.28 3.93 Normative SMU (max. 1 criterion) ref. (a) 19.61 ref. (a) 29.57 ref. (a) 24.39 ref. (a) 15.09 Risky SMU (2 to 5 criteria) 0.50*** (b) 0.06 1.64 28.61 0.75*** (b) 0.06 2.11 46.94 0.55*** (b) 0.06 1.73 35.76 0.78*** (b) 0.07 2.18 27.96 Problematic SMU (6 to 9 criteria) 0.95*** (c) 0.15 2.58 38.61 1.25*** (c) 0.14 3.48 59.38 0.90*** (b) 0.15 2.47 44.36 1.58*** (c) 0.16 4.85 46.30 Notes. SMU = social media use; OR = odds ratios frommultivariate logistic regression, controlled for gender, age, education level, and ethnic background; SE = standard error; M% = margin, i.e. expected probability while holding all covariates at their means; Ref. = reference category. Rows with different letters denote significant group differences at p < 0.05 with Bonferroni correction. 1 Borderline / abnormal range of emotional problems (score 5 or higher out of 10). 2 Borderline / abnormal range of conduct problems (score 4 or higher out of 10). 3 Borderline / abnormal range of hyperactivity (score 7 or higher out of 10). 4 Borderline / abnormal range of peer problems (score 4 or higher out of 10). 5 Does not like school very much or not at all. 6 Feels some or a lot pressure by schoolwork. 7 Average sleep duration on weekdays does not meet the age-specific recommendation. 8 An average score of 3.5 or higher on five items from the Groningen Sleep Quality Scale. * p < 0.05, ** p < 0.01, *** p < 0.001.