Raymond H. Baillargeon

Developmental pathways leading to externalizing behaviors in 5 year olds born before 29 weeks of gestation

&NA; Longitudinal data for 62 infants born before 29 weeks of gestation were used to assess the influence of four factors (i.e., neonatal health, family environment, language skill, and nonverbal ability) on the parental report of hyperactive and oppositional behaviors of children at 5 years 9 months. The proposed path analysis model tested the following: (1) whether neonatal health and family environment have a direct influence on language skill and nonverbal ability both measured at 18 months corrected age, (2) the predictive value of language skill and nonverbal ability on oppositional and hyperactive behaviors, and (3) whether the effects of neonatal health and/or family environment on oppositional and hyperactive behaviors can be conceived as mediated by language skill and/or nonverbal ability. The results revealed three main pathways. First, family environment predicted language skill, which, in turn, was negatively associated with childrens hyperactivity. Second, neonatal health predicted nonverbal ability, which was positively linked to oppositional behaviors. Third, a direct negative relation between neonatal health and hyperactive outcome was observed. The implications of these substantially different pathways for hyperactive and oppositional behaviors are discussed.

The Development of Prosocial Behaviors in Young Children: A Prospective Population-Based Cohort Study

ABSTRACT Researchers know relatively little about the normative development of childrens behaviors aimed at alleviating distress or discomfort in others. In this article, the authors aim to describe the continuity and discontinuity in the degree to which young children in the general population are reported to exhibit specific prosocial behaviors. Data came from the Québec Longitudinal Study of Child Development. Consistent with Hays model of prosocial development, the results show that there were about as many children who stopped exhibiting prosocial behaviors between 29 and 41 months of age as there were children who started doing so during this period. Further, gender differences (girls > boys) in prosocial behaviors are either emerging or at least increasing in magnitude, with girls being more likely to start and boys being more likely to stop exhibiting these behaviors between 29 and 41 months of age. Consistent with the early-onset hypothesis, children who exhibit prosocial behaviors at 17 months of age are less likely to stop exhibiting the same behaviors between 29 and 41 months of age. Otherwise, if they did not exhibit prosocial behaviors at 29 months of age, they are also more likely to start doing so in the following year.

DEVELOPMENT OF DISRUPTIVE BEHAVIORS IN YOUNG CHILDREN: A PROSPECTIVE POPULATION-BASED COHORT STUDY

We know relatively little about the development of disruptive behaviors (DBs), and gender differences therein. The objective of this study was to describe the continuity and discontinuity in the degree to which young children in the general population are reported to exhibit specific DBs over time. Data came from the Québec Longitudinal Study of Child Development. First, the results show that relatively few children exhibit DBs on a frequent basis at 41 months of age. Second, the results show that a majority of children who exhibit a particular DB on a frequent basis at 41 months of age did not do so 1 year earlier. In addition, a majority of children who exhibited a particular DB on a frequent basis at 29 months of age no longer do so 1 year later. Third, gender differences in DBs (boys > girls) are either emerging or at least increasing in magnitude between 29 and 41 months of age. Consistent with the canalization of the behavioral development principle, children who exhibited DBs on a frequent basis at 29 months of age are less likely to stop doing so in the following year if they had exhibited the same behaviors at 17 months of age.

Individual Change in Methylphenidate Use in a National Sample of Children Aged 2 to 11 Years

Objectives: To determine methylphenidate use in children aged 2 to 13 years. To provide age- and sex-specific estimates of methylphenidate initiation and cessation during a 2-year period. Method: Data from 2 cycles of a Canadian household survey yielded a sample of over 10 000 children aged 2 to 11 years at Cycle 1 who continued to participate at Cycle 2. We used logit modelling to estimate Cycle 2 methylphenidate use, methylphenidate use over a 2-year period, and methylphenidate initiation and cessation from Cycles 1 to 2. Results: In 1996 and 1997, methylphenidate use ranged from 0.32% to 6.31% among children aged 4 to 13 years. School-aged boys were more likely than girls to use methylphenidate. Odds were greater for boys aged 6 to 7 years than for boys aged 4 to 5 years; they were also greater for boys aged 10 to 11 years than for boys aged 12 to 13 years. Almost 1% of children used methylphenidate at both data cycles. Odds of Cycle 2 methylphenidate use were 135 times greater for children using methylphenidate at Cycle 1, compared with nonusers. Methylphenidate initiation ranged from 0.20% to 3.34%, and school-aged boys had higher initiation rates than girls. Cessation rates ranged from 18% to 78%, and there were no statistically significant differences by age and sex. Conclusions: Methylphenidate prevalence findings are consistent with past studies. We found an age-by-sex interaction on methylphenidate use. We also found both continuity and discontinuity in methylphenidate use.

A Multidimensional Approach to Disruptive Behaviors: Informing Life Span Research from an Early Childhood Perspective

The historical use of categorical diagnoses of disruptive behavior syndromes and disorders has been integral to clinical identification, treatment, and service utilization. The major nosological frameworks for classification have been the Diagnostic and Statistical Manual (DSM) (American Psychiatric Association, 2000) and International Classification of Diseases (World Health Organization, 2000). Increasingly, however, there is consensus that categorical approaches, which rely on an array of symptom criteria to classify an individual as having or not having a single disorder, may not fully capture clinical and developmental patterns of disruptive behaviors across the life cycle (Baillargeon, Zoccolillo, et al., 2007; Frick & White, 2008; Maughan, 2005; Rutter, 2003; Wakschlag et al., 2011). In contrast, multidimensional conceptualizations of psychopathology, which incorporate more than one domain or dimension of behavior and assess each domain/dimension along a continuum, offer many unique advantages to clinical characterization of disruptive behavior, including (1) improved characterization of heterogeneity, (2) provision of alternative strategies for understanding developmental course, (3) parsing the manner in which different components or dimensions of disruptive behavior may have varying associations with co-occurring symptoms, and (4) linkage of specific dimensions relevant to disruptive behavior to neurobiologic mechanisms as well as family and ecological contextual factors.

The burden of disability in children and youths associated with impairments of psychological functions.

The immense burden of health conditions in children that is associated with mental disorders worldwide is increasingly being recognized. In comparison, the burden of disability associated with childrens impairments of psychological functions (IPFs) is not well documented. The goal of this population-based study was to derive a measure of the burden of disability in children associated with IPFs that takes into account the highly variable impact such impairments might have on childrens everyday activities. Data came from the 2001 Participation and Activity Limitation Survey, a national survey of individuals with disabilities living in Canada. Latent class analysis was used to obtain a maximum likelihood estimate of the proportion of children with IPFs living in Canada who were severely limited in their everyday activities, by age and sex. As expected, the burden of disability was not evenly shared among children with IPFs. In fact, only a minority of children with IPFs were severely limited in their everyday activities. This represents approximately 15% of 5-14year-old boys with a disability and 10% of their female counterparts living in Canada. These estimates provide a better appraisal of the burden of disability in children associated with IPFs than previous estimates, which only considered the presence or absence of IPFs.

Obstetrical complications and physical aggression behaviours before the age of 2

Obstetrical Complications and Physical Aggression Behaviours Before the Age of 2 Objective: To determine if infants who experienced obstetrical complications (OCs) have a greater tendency to show frequent physical aggression behaviours before the age of 2, independent of gender and family income. Another objective was to explain, at least partly, the sexual differences found in some behaviours using OCs. Method: Data were from the Québec Longitudinal Study of Child Development (QLSCD). OCs were measured with Agpar scores (< 7) at 1 minute following birth. Family income level— sufficient or not—was measured when infants were about 5 months old. Twelve behaviours of physical aggression, opposition defiance, and hyperactivity were measured when infants were about 17 months old. Weighted data were analyzed using hierarchical log-linear models. Results: Results suggest that infants with an Agpar score of less than 7 after birth are generally more likely to frequently display aggressive behaviours at 17 months, independent of gender and family income. Further, these results suggest it may be possible to explain, by OCs, the greater tendency in boys to frequently display aggressive behaviours at 17 months. Conclusions: Contrary to some hypotheses, it turns out that OCs have an impact on aggressive behaviours before the age of 2 independent of socioeconomic status.OBJECTIVE To determine if infants who experienced obstetrical complications (OCs) have a greater tendency to show frequent physical aggression behaviours before the age of 2, independent of gender and family income. Another objective was to explain, at least partly, the sexual differences found in some behaviours using OCs. METHOD Data were from the Québec Longitudinal Study of Child Development (QLSCD). OCs were measured with Agpar scores (< 7) at 1 minute following birth. Family income level—sufficient or not—was measured when infants were about 5 months old. Twelve behaviours of physical aggression, opposition defiance, and hyperactivity were measured when infants were about 17 months old. Weighted data were analyzed using hierarchical log-linear models. RESULTS Results suggest that infants with an Agpar score of less than 7 after birth are generally more likely to frequently display aggressive behaviours at 17 months, independent of gender and family income. Further, these results suggest it may be possible to explain, by OCs, the greater tendency in boys to frequently display aggressive behaviours at 17 months. CONCLUSIONS Contrary to some hypotheses, it turns out that OCs have an impact on aggressive behaviours before the age of 2 independent of socioeconomic status.