Maartje Boer

CHAPTER 7 212 of following the trajectories of Classes 1, 2, or 3, relative to Class 4. For reference, additional findings from stepwise analyses can be consulted in the Appendix (Tables A7.2-A7.4). Table 7.4 Observed Means and Proportions Study Variables, by Class (n = 1,419) Pooled sample Class 1: Variably high problematic SMU, variably high SMU frequency Class 2: Persistently high problematic SMU, persistently average SMU frequency Class 3: Persistently low problematic SMU, persistently low SMU frequency Class 4: Persistently low problematic SMU, variably high SMU frequency M/% SD M/% SD M/% SD M/% SD M/% SD Controls Girl 45.9% 58.0% 35.7% 30.8% 51.4% Pre-vocational education 57.8% 70.0% 59.8% 50.3% 53.3% Intermediate education 28.5% 22.0% 30.4% 29.9% 31.3% Pre-university education 13.7% 8.0% 9.8% 19.8% 15.4% Immigrant background 1 21.8% 21.4% 26.8% 22.6% 19.5% Subjective wellbeing Life satisfaction 1 4.661 0.595 4.449 0.644 4.500 0.616 4.786 0.558 4.796 0.512 Self-esteem 1 3.815 0.491 3.701 0.503 3.668 0.489 3.944 0.474 3.877 0.462 Self-control Attention deficit 1 2.285 0.526 2.555 0.507 2.383 0.490 2.081 0.501 2.188 0.485 Impulsivity 1 1.918 0.484 2.204 0.513 1.989 0.447 1.676 0.388 1.843 0.428 Social competencies Perceived friendship competence 1 4.321 0.460 4.324 0.430 4.035 0.510 4.297 0.477 4.454 0.383 Notes. SMU = social media use; M = mean ; SD = standard deviation. 1 Proportion, means, and standard deviations for the pooled sample slightly differ from those reported in the sample description and Table 7.1. This is because the present table presents the proportions, means, and standard deviations based on the imputed data, whereas Table 7.1 presents the proportions, means and standard deviations based on the complete data. Class 1: Variably High Problematic SMU, Variably High SMU Frequency Figure 7.4 shows that compared to Class 4, girls and pre-vocational educated adolescents were more likely to be in Class 1 than boys and pre-university