A longitudinal investigation into the relations between personality, sleep, conduct problems, and school performance in adolescents

Abstract

Introduction: Different lines of research suggest that disturbed sleep is particularly detrimental during adolescence because it may contribute to emotional and behavioral disorders (e.g., Dahl & Harvey, 2007) and impair school performance (e.g., Wolfson & Carskadon, 2003). However, previous investigations were often limited in three respects: (a) They used cross-sectional rather than longitudinal designs, thereby precluding causal inference; (b) they did not take into account possible interactions with personality dimensions, in particular, the different facets of impulsivity; and (c) they relied on self-reported rather than on actual school grades. The present study sought to overcome these limitations. Methods: A sample of 202 7th to 9th graders aged 12 to 16 years completed five questionnaires at an interval of 6 months: the short version of the Big Five Personality Inventory (Rammstedt & John, 2007), the UPPS Impulsive Behavior Scale (Whiteside & Lynam, 2001), the Insomnia Severity Index (Morin, 1993), the Multidimensional Fatigue Inventory (Smets et al., 1995), and the Strengths and Difficulties Questionnaire (Goodman, 2001). In addition, the school provided the grades that the adolescents obtained during the ongoing scholastic year. Results: Insomnia severity and fatigue were correlated to emotional and behavioral problems (r range = .48 to .65, p<.001), as well as to school grades (r range = .22 to .23, p<.01). Five domains of personality were also correlated to emotional and behavioral problems: agreeableness (r range = -.32 to -.38, p<.001), conscientiousness (r range = -.38 to -.42, p<.001), neuroticism (r range = .44 to .48, p<.001), impulsive urgency (r range = .57 to .60, p<.001), and lack of perseverance (r range = .45 to .51, p<.001). Moreover, the latter two facets were correlated to school grades (r = -.18 to -.28, p<.01). Follow-up longitudinal structural equation models were computed to map the relations between the variables of interest across time. Conclusion: The present findings support the notions that (a) disturbed sleep contributes to emotional and behavioral problems and to poor school performance in adolescents, and (b) the relations between sleep and behavioral measures are impacted by interindividual differences in personality.