Michel Janosz

Learn More
We first replicated the data analytic strategy used in Duncan et al. (2007) with a population-based data set of French-speaking children from Quebec (Canada). Prospective associations were examined between cognitive, attention, and socioemotional characteristics underlying kindergarten school readiness and second grade math, reading, and general(More)
Although the concept of school engagement figures prominently in most school dropout theories, there has been little empirical research conducted on its nature and course and, more importantly, the association with dropout. Information on the natural development of school engagement would greatly benefit those interested in preventing student alienation(More)
PURPOSE We prospectively tested the extent to which witnessing school violence predicts psychosocial and school adjustment in students while accounting for their prior psychosocial characteristics and peer victimization. We also explored the role of feelings of insecurity in explaining this relationship. METHODS Questionnaires were administered to 1104(More)
Childhood disruptiveness is one of the most important antecedents of heavy substance use in adolescence, especially among boys. The first aim of the present study is to verify whether parental monitoring and friend conventionality protect disruptive boys from engaging in heavy substance-use in adolescence. The second purpose is to examine whether these(More)
BACKGROUND Research has raised significant concern regarding the affective consequences of synthetic drug use. However, little evidence from well-controlled longitudinal studies exists on these consequences. The aim of this study was to determine whether use of meth/amphetamine (speed) and ±3,4-methylenedioxymethamphetamine (MDMA, ecstasy) is independently(More)
Self-esteem and body image are central to coping successfully with the developmental challenges of adolescence. However, the current knowledge surrounding self-esteem and body image is fraught with controversy. This study attempts to clarify some of them by addressing three questions: (1) Are the intraindividual developmental trajectories of self-esteem and(More)
OBJECTIVE To identify childhood body mass index (BMI) trajectories and to describe their association with subsequent academic and cognitive outcomes. STUDY DESIGN Prospective cohort: Height and weight measured annually from 4 to 7 years. A mixture of regressions approach grouped children into BMI trajectories (n=1959 children; n=5754 BMI measures).(More)
BACKGROUND Questions remain regarding the consequences of illicit drug use on adolescent adjustment and the nature of mechanisms that may explain these consequences. In this study, we examined whether early-onset illicit drug use predicts subsequent academic and psychosocial adjustment and whether associations are socially-mediated by decreased school(More)
BACKGROUND High school dropout represents an important public health issue. This study assessed the 3 distinct dimensions of student engagement in high school and examined the relationships between the nature and course of such experiences and later dropout. METHODS We administered questionnaires to 13,330 students (44.7% boys) from 69 high schools in the(More)
PURPOSE Increasing evidence suggests the existence of heterogeneity in the development of depressive symptoms during adolescence, but little remains known regarding the implications of this heterogeneity for the development of commonly co-occurring problems. In this study, we derived trajectories of depressive symptoms in adolescents and examined the(More)