The Development of Physical Aggression from Toddlerhood to Pre-Adolescence: A Nation Wide Longitudinal Study of Canadian Children

Abstract

The objectives of the study were to model the developmental trajectories of physical aggression (PA) from toddlerhood to pre-adolescence and to identify risk factors that distinguish typical (normative) from atypical developmental patterns. Ten cohorts of approximately 1,000 children (n = 10,658) drawn form a nationally representative (Canadian) sample were followed over 6 years. Using a group-based trajectory approach, we identified three groups of children with distinct developmental trajectories between 2 and 11 years of age. One third of the children (31.1%) followed a low desisting trajectory, reflected in infrequent use of PA in toddlerhood and virtually no PA by pre-adolescence. The majority of children (52.2%) followed a moderate desisting trajectory, reflected in occasional use of PA in toddlerhood and infrequent use by pre-adolescence. One sixth of the children (16.6%) followed a high stable trajectory of PA. Multivariate logistic regression indicated that children in the high PA trajectory group were more likely to be boys (OR: 1.67; CI: 1.5-1.87), from low income families (OR: 1.4; CI; 1.27-1.67), from families where the mother had not completed high school (OR: 1.20; CI: 1.05-1.38) and who reported using hostile/ineffective parenting strategies (OR: 1.16; CI: 1.14-1.18). In sum, the results indicate that the typical developmental pattern of PA was one of occasional and declining use over time. However, about one sixth of children, mostly boys from disadvantaged families, exhibited an atypical developmental pattern reflected in more frequent and stable use of PA. The results suggest that most children learned relatively well to inhibit PA by the end of childhood and that a minority failed to do so. Family risks traditionally found to be associated with antisocial behaviors during adolescence appear to interfere with the socialization of PA during early and middle childhood.

Developmental Links Between Trajectories of Physical Violence, Vandalism, Theft, and Alcohol-Drug Use from Childhood to Adolescence

“…As expected, females were less likely than males to follow the high physical violence trajectory, in addition to, on average, being less physically aggressive from age 6 onwards. These findings support previous research on physical aggression (Bongers et al 2004;Côté et al 2006;NICHD 2004) and may suggest that girls learn more rapidly than boys to control their use of physical aggression and learn to express conflict in more socially acceptable manners (Côté et al 2007;NICHD 2004;Tremblay 2003). In contrast to physical violence, trajectories of vandalism, theft, and alcohol-drug use were characterized by, on average, low levels at age 10, but increasing levels into adolescence, which supported previous research (Bongers et al 2004;Chassin et al 2004;Chassin et al 2002;Lacourse et al 2002).…”

“…As stated previously, youth following the high physical violence trajectory were already highly physically aggressive in childhood (see also Côté et al 2006;NICHD 2004;Nagin and Tremblay 1999). Thus, early onset cases, who are likely males, engage in high levels of all types of ASB.…”

“…As stated previously, studies have shown that physical aggression peaks in early childhood and declines thereafter for the majority of children (Archer and Côte 2005;Broidy et al 2003;Côté et al 2006;NICHD Early Child Care Research Network 2004). However children on a high trajectory of physical aggression throughout the elementary school years will use most other forms of antisocial behavior such as theft, and vandalism (Broidy et al 2003;Côté et al 2006;Nagin and Tremblay 1999), which typically increase in adolescence (Bongers et al 2004). Therefore, and given the stability of ASB for early onset youth, it is unlikely that these individuals simply cease to be physically aggressive.…”

“…It is well established that high levels of ASBs are most prevalent in boys during childhood Bongers et al 2004;Broidy et al 2003;Côté et al 2006Côté et al , 2007Crick and Zahn-Waxler 2003;van Lier et al 2005). However, such differences may diminish with age as Moffitt and colleagues found that males and females are most alike in their level of ASB in mid-adolescence.…”

Contingent responses of mothers and peers to indirect and direct aggression in preschool and school‐aged children

“…That is, based on several lines of evidence, a decline in physical aggression across the age groups should be expected (c.f. Côté et al, 2007;Côté, Vaillancourt, LeBlanc, Nagin, & Tremblay, 2006;Nagin & Tremblay, 1999). If the mothers enrolled in the present study are more punitive than the general population, and if punitive discipline results in persistent physical aggression in the early elementary school years, the physical discipline reported by the mothers and children in the current study might account for the failure to identify an age effect on the forms of aggression.…”