Risk factors associated with boys’ and girls’ developmental trajectories of physical aggression from early childhood through early adolescence
Article [Version publiée]
Résumé·s
IMPORTANCE This study used multitrajectory modeling to identify distinct trajectories of physical
aggression from ages 1.5 to 13 years for boys and girls.
OBJECTIVES To trace the development of boys’ and girls’ physical aggression problems from infancy
to adolescence using mother ratings, teacher ratings, and self-ratings and to identify early family
predictors of children on the high physical aggression trajectories.
DESIGN, SETTING, AND PARTICIPANTS This cohort study used data from the Quebec Longitudinal
Study of Child Development (QLSCD), a study of a representative, population-based sample of 2223
infants born in 1997 and 1998 in the Canadian province of Quebec. The dates of analysis were
January 2017 to January 2018.
MAIN OUTCOMES AND MEASURES Trained research assistants conducted 7 interviews (at child
ages 1.5, 2.5, 3.5, 4.5, 5, 6, and 8 years) with the person most knowledgeable about the child
(mothers in 99.6% [2214 of 2223] of cases). Teachers assessed the child’s behavior at ages 6, 7, 8, 10,
12, and 13 years. Self-reports of behavior problems were obtained from the child at ages 10, 12, and
13 years.
RESULTS The sample included 2223 participants, 51.2% of whom were boys and 91.2% of whom
were of white race/ethnicity. The mean response rate for mother ratings of physical aggression
during the first 8 years of life was 80.9% (range, 65.1%-91.7%). For teacher ratings of physical
aggression from ages 6 to 13 years, the mean response rate was 45.7% (range, 35.4%-56.9%), while
the mean response rate of physical aggression assessment from self-ratings between ages 10 and
13 years was 57.9% (range, 55.2%-60.5%). Attrition was higher among families with low
socioeconomic status and single-parent families, as well as among young mothers and mothers who
were not fluent in French or English. A statistical analysis to examine the consequences of attrition
was included. For boys and girls, the frequency of physical aggressions increased from age 1.5 years
(2039 [91.7%]) to age 3.5 years (1941 [87.3%]) and then substantially decreased until age 13 years
(1228 [55.2%]). Three distinct developmental trajectories of physical aggression were observed for
girls and 5 for boys. Most family characteristics measured at 5 months after the child’s birth were
associated with a high physical aggression trajectory for boys and girls.
CONCLUSIONS AND RELEVANCE Family characteristics at 5 months after the child’s birth could be
used to target preschool interventions aimed at preventing the development of boys’ and girls’
chronic physical aggression problems.