Quebec Longitudinal Study Of Child Development Research Articles

The intergenerational continuity of alcohol use in a population sample

IntroductionResearch shows that parental alcohol use predicts youths’ alcohol use, but this intergenerational continuity may vary across countries, and little is known about its moderators. This study examined for the first time the intergenerational continuity in alcohol use in a population sample of families in Canada, and tested whether it varied by youths’ sex, family income, or family structure. MethodsWe used prospective longitudinal data on 1632 families from the Quebec Longitudinal Study of Child Development (QLSCD), a representative sample from the province of Quebec, Canada. Youths self-reported alcohol use and binge drinking frequency at seven timepoints from early adolescence to early adulthood. Predictors were mothers’ and fathers’ self-reported alcohol use from youths’ infancy through age 13, and mother-reported socioeconomic variables. ResultsWe identified three trajectories of alcohol use from ages 13 to 21 years: normative, late-onset and early-onset. Maternal alcohol use increased the youths' risk of following the early-onset trajectory of alcohol use, while both parents’ alcohol use decreased the odds of the youths following the late-onset trajectory, compared to the normative trajectory. Insufficient family income increased youths' risk of following either the early-onset or late-onset trajectories. Mothers’ and fathers’ alcohol use did not interact in predicting youths’ trajectory, and we found no moderating effects of the youths’ sex, insufficient income, or years as a single-parent family. ConclusionThe results suggest modest intergenerational continuity of alcohol use in Quebec families which may be used, with income insufficiency, to help identify at-risk children for targeted interventions.

Longitudinal Association Between the Quality of the Separated Parents’ Relationship and the Frequency of Father–Child Contact: The Mothers’ Perspective

This longitudinal study is based on family systems theory and aims to explore the association between the quality of the separated parents’ relationship and the frequency of father–child contact up to five years after parental separation. Using data collected from 408 families from the Quebec Longitudinal Study of Child Development (QLSCD), multilevel analyses and latent growth curve model were carried out. The results highlight a positive association between the separated parents’ relationship and father–child contact and demonstrate the impact of the initial contact frequency on the evolution over time of the separated parents’ relationship. They also highlight the contribution of custody tension, the child’s age, the length of time the couple lived together, and the socio-economic status on the initial levels of the studied trajectories.

Associations between family functioning during early to mid-childhood and weight status in childhood and adolescence: findings from a Quebec birth cohort.

Impaired family functioning has been associated with obesity in children and adolescents, but few longitudinal studies exist. We examined whether family functioning from early to mid-childhood is associated with overweight and obesity in later childhood and adolescence. We examined data from the Quebec Longitudinal Study of Child Development (QLSCD), a birth cohort (N = 2120), collected between 1998 and 2011. Parent-reported family functioning was assessed at 4 time points between ages 0.5 and 8 years using the McMaster Family Assessment Device with established cut-offs for impaired family functioning. Participants were classified as having experienced: 1) early-childhood impaired functioning, 2) mid-childhood impaired functioning, 3) both early and mid-childhood impaired functioning, or 4) always healthy family functioning. Overweight and obesity were determined at 10- and 13-years using WHO criteria. Covariate adjusted multinomial logistic regressions were fitted to the data to examine associations between longitudinal family functioning groups (using the always healthy functioning as reference category) and the likelihood of having overweight and obesity (vs normal weight) at ages 10 (n = 1251) and 13 years (n = 1226). In the 10- and 13-year sub-samples, respectively 10.2% and 12.5% of participants had experienced both early and mid-childhood impaired family functioning. Participants in this group had an increased likelihood of having obesity (vs normal weight) at age 10 years [OR = 2.63 (95% CI: 1.36; 5.08)] and at age 13 years [OR = 1.94 (95% CI: 0.99; 3.80] compared to those in the always healthy functioning group. No associations were found for other family functioning categories or for overweight status. Approximately one in ten children experienced impaired family functioning throughout early and mid-childhood. Findings suggest a link between impaired functioning across childhood and the development of obesity at 10 years of age and possibly at 13 years of age.

Cohort Profile: Quebec Longitudinal Study of Child Development (QLSCD).

The Quebec Longitudinal Study of Child Development (QLSCD) was designed to examine the long-term associations of preschool physical, cognitive, social, and emotional development with biopsychosocial development across childhood, adolescence, and young adulthood. QLSCD is an ongoing prospective cohort including 2120 singletons born in 1997/1998 in the Canadian province of Quebec. So far, data have been collected annually or every 2years from child ages 5months to 21years. The cohort currently includes 1245 participants. Data available include a range of environmental (e.g., family characteristics, child behaviour, educational attainment, mental health), biological (e.g., hair cortisol, genetic, epigenetic), and administrative data. QLSCD has contributed to the understanding of children's psychosocial development, including the development of physical aggression and anxiety. QLSCD articles have advanced scientific knowledge on the influence of early childhood factors on childhood, adolescent, and young adult mental health, including the effect of participation in early childcare on cognitive and behavioural development, the developmental origins of adolescent and young adult mental health problems and suicide risk, and the development of interpersonal difficulties (e.g., peer victimisation) from preschool years to adolescence. QLSCD has given major contributions to our understanding of the link between different aspects of child development and biopsychosocial development during the first two decades of life. Unique features include the presence of environmental, biological, and administrative data, long-term follow-up with frequent data collections, and use of data from multiple informants, including teachers, mothers, fathers, and the children themselves.

Developmental profiles of childhood attention-deficit/hyperactivity disorder and irritability: association with adolescent mental health, functional impairment, and suicidal outcomes.

Irritability is frequently comorbid with ADHD. Although irritability alone has been linked to deleterious mental health and adaptive issues, the joint developmental course of ADHD and irritability symptoms during childhood as well as its association with later mental health and suicidal outcomes is not fully understood. We aimed to describe the developmental trajectories of childhood ADHD and irritability symptoms and to quantify their association with adolescent mental health and suicidal outcomes. The Quebec Longitudinal Study of Child Development (QLSCD) included 1407 participants from the general population followed up from age 5months to 17years. We used a multitrajectory approach to identify developmental trajectories of childhood (6-12years) ADHD and irritability symptoms. Outcome measures were adolescent (13-17years) mental health (psychiatric symptoms/functional impairment) and suicidal outcomes. We identified distinct developmental profiles: combined absent or very low ADHD and absent or very low irritability (940 [66.8%]; reference group), moderately high irritability and low ADHD (158 [11.2%]), moderately high ADHD and low irritability (198 [14.1%]), and combined high ADHD and high irritability (111 [7.9%]). Multivariate modeling showed that, compared to children in the reference group, those in the combined high ADHD and high irritability profile showed higher levels of ADHD continuity (d ranges=0.40-0.50), externalizing (d ranges=0.25-0.59), internalizing (d ranges=0.20-0.29), and functional impairments (d ranges=0.17-0.48) and suicidal behaviors (odds ratio (OR)=2.12, confidence interval (CI)=1.47-3.06) in adolescence. The presence of persistently high levels of irritability along with ADHD symptoms during childhood significantly predicts adolescent ADHD continuity, externalizing, internalizing, and suicidal outcomes. Systematic consideration of irritability when assessing and treating ADHD may improve long-term mental health outcomes.

Cybervictimization in adolescence and its association with subsequent suicidal ideation/attempt beyond face-to-face victimization: a longitudinal population-based study.

Cross-sectional associations have been documented between cybervictimization and suicidal risk; however, prospective associations remain unclear. Participants were members of the Quebec Longitudinal Study of Child Development (QLSCD), a prospective birth cohort of 2,120 individuals followed from birth (1997/98) to age 17years (2014/15). Cybervictimization and face-to-face victimization experienced since the beginning of the school year, as well as serious suicidal ideation and/or suicide attempt were self-reported at ages 13, 15 and 17years. In cross-sectional analyses at 13, 15 and 17years, adolescents cybervictimized at least once had, respectively, 2.3 (95% CI=1.64-3.19), 4.2 (95% CI=3.27-5.41) and 3.5 (95% CI=2.57-4.66) higher odds of suicidal ideation/attempt after adjusting for confounders including face-to-face victimization, prior mental health symptoms and family hardship. Sensitivity analyses suggested that cybervictimization only and both cyber- and face-to-face victimization were associated with a higher risk of suicidal ideation/attempt compared to face-to-face victimization only and no victimization; however, analyses were based on small n. In prospective analyses, cybervictimization was not associated with suicidal ideation/attempt 2years later after accounting for baseline suicidal ideation/attempt and other confounders. In contrast, face-to-face victimization was associated with suicidal ideation/attempt 2years later in the fully adjusted model, including cybervictimization. The cross-sectional association between cybervictimization and suicidal ideation/attempt is independent from face-to-face victimization. The absence of a prospective association suggested short-term effects of cybervictimization on suicidal ideation/attempt.

Psychopathic Traits in Middle Childhood: Evidence of a Hierarchical Three-Factor Structure

Although the development of psychopathy is not well understood, prior studies suggest that psychopathic traits begin to develop in childhood. Whereas research suggests consistency in the structure and correlates of psychopathic traits as assessed with clinical measures of psychopathic traits in adolescence and in adulthood, there is less agreement about the nature of psychopathic traits earlier in childhood. This study was designed to enhance understanding of the nature of psychopathic traits in youth by: 1) examining the fit of one, two, three, and four factor models of psychopathic traits during middle childhood, and 2) examining the stability of the factor structure of psychopathic traits over time through invariance testing. The participants were youth in the Quebec Longitudinal Study of Child Development (QLSCD) whose teachers provided ratings on 17 items associated with four validated dimensions of psychopathy at six (N = 605), seven (N = 747) and eight years of age (N = 686). Confirmatory factor analyses revealed that a hierarchical three-factor model of psychopathic traits, consisting of interpersonal, affective, and lifestyle/ antisocial components provided the best fit to the data at all three ages. Analyses also demonstrated strong invariance across these ages. These findings provide preliminary evidence that the internal structure for a syndrome of psychopathic traits in middle childhood is somewhat similar but slightly less differentiated than the factor structure identified during adolescence. Current findings also suggest that this internal structure is stable over a three-year period during middle childhood.

Risk Factors Associated With Boys’ and Girls’ Developmental Trajectories of Physical Aggression From Early Childhood Through Early Adolescence

This study used multitrajectory modeling to identify distinct trajectories of physical aggression from ages 1.5 to 13 years for boys and girls. 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. 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. 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. 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. 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.

Explaining school entry math and reading achievement in Canadian children using the Opportunity-Propensity framework

The Opportunity–Propensity framework predicts that academic success is a function of: (a) Antecedent; (b) Opportunity; and (c) Propensity factors. The aim of the present study was to replicate and expand the O-P framework model with a population-based representative sample of French-Canadian children. The sample consisted of 2120 children followed in the context of the Quebec Longitudinal Study of Child Development (QLSCD). Structural equation models revealed that the O-P framework provided a good fit to the Canadian data and predicted 55 and 51% of the variance in kindergarten math and verbal achievement, respectively. Furthermore, the addition of previously unexamined antecedent (i.e., gestational smoking), opportunity (i.e., home literacy activities), and propensity (i.e., motor skills) predictors contributed significant variance to the model. Similarities and differences between the Canadian findings and those obtained with American samples are discussed in terms of social policy and intervention programs.

Physical aggression and language ability from 17 to 72 months: cross-lagged effects in a population sample.

BackgroundDoes poor language ability in early childhood increase the likelihood of physical aggression or is language ability delayed by frequent physical aggression? This study examined the longitudinal associations between physical aggression and language ability from toddlerhood to early childhood in a population sample while controlling for parenting behaviours, non-verbal intellectual functioning, and children’s sex.MethodsChildren enrolled in the Quebec Longitudinal Study of Child Development (QLSCD) (N = 2, 057) were assessed longitudinally from 17 to 72 months via parent reports and standardized assessments.ResultsThe cross-lagged models revealed modest reciprocal associations between physical aggression and language performance from 17 to 41 months but not thereafter.ConclusionsSignificant associations between physical aggression and poor language ability are minimal and limited to the period when physical aggression and language performance are both substantially increasing. During that period parenting behaviours may play an important role in supporting language ability while reducing the frequency of physical aggression. Further studies are needed that utilize multiple assessments of physical aggression, assess multiple domains of language abilities, and that examine the potential mediating role of parenting behaviours between 12 and 48 months.

Tracking exposure to child poverty during the first 10 years of life in a Quebec birth cohort.

Early childhood poverty is associated with adult chronic diseases. The objectives of this study were to examine patterns of exposure to poverty during the first 10 years of life in the Quebec Longitudinal Study of Child Development (QLSCD) cohort according to three measures of poverty and to explore family characteristics associated with different poverty exposures. Data from 1,334 participants from the QLSCD were collected annually at home from ages 5 months through 10 years. Household income (previous 12 months) and sources of income were recorded at each data round. Poverty status was operationalized as 1) living below the low income cut-off of Statistics Canada, 2) receiving social welfare and 3) being in the lowest quintile of socio-economic status. We plotted trends in the prevalence of child poverty over time. We used latent class growth modelling to identify subgroups with similar poverty trajectories. Duration of poverty according to each measure was computed separately for early childhood, middle childhood, and the entire 10 years of life. Four trajectories of poverty were identified: stable poor, decreasing likelihood, increasing likelihood, and never poor. The three measures of poverty do not cover the same population, yet the characteristics of those identified as poor are similar. Children of non-European, immigrant mothers were most likely to be poor, and there was a higher likelihood of children from single-parent families to live in chronic poverty during the first 10 years. A large proportion of children are exposed to poverty before 10 years of age. More effective public policies could reduce child poverty.

The influence of poverty and social support on the perceived health of children born to minority migrant mothers

Objective. Poverty and low social support are common among minority migrant families. Little is known about their impact on the health of children of minority migrants to Canada. This study examined the associations between maternal perception of child's health and migration status, and examined the specific role of poverty and low social support in these associations. Design. Data from the first two rounds of the Quebec Longitudinal Study of Child Development (QLSCD) were analysed. The sample included 1990 children at 17 months of age, classified according to their mother's migration status: children of minority migrant mothers (n=165) and Canadian-born mothers (n=1825). Maternal perception of child's health status and social support were measured at 17 months, household income was measured at 5 and 17 months. Multivariable logistic regressions were performed; interactions of migration status with poverty and social support were tested. Results. Poverty and low social support were more common among minority migrant mothers than among Canadian-born mothers. Children of minority migrant mothers who were ‘never poor’ and reported high levels of social support were perceived in better health (OR 0.42; 95% confidence interval (CI): 0.19–0.91) than children of Canadian-born mothers (reference group). In contrast, children of minority migrant mothers who were ‘always poor’ and reported low social support were perceived in worse health (OR 6.32; 95% CI: 1.69–23.71) compared to the reference group. Conclusion. In Quebec, economic hardship and lack of social support are common realities among minority migrants with young children. Combined exposure to poverty and low social support is most detrimental to the perceived health of children of minority migrants.

Poverty and Chronic Illness in Early Childhood: A Comparison Between the United Kingdom and Quebec

Our goal was to examine the association between poverty, in the first and fourth years of life and cumulatively in the first and fourth years of life, and the health of children in the fourth year of life in the UK Millennium Cohort Study and in the Quebec Longitudinal Study of Child Development (QLSCD). Data from the UK Millennium Cohort Study of 14 556 children and from the QLSCD of 1950 children were analyzed. Comparable measures of poverty were households in receipt of the safety-net benefit: income support in the United Kingdom and social welfare in Quebec. Three parent-reported health indicators were examined: asthma attack, long-standing illness, and limiting long-standing illness by the fourth year of life. Associations were explored with logistic regression modeling controlling for child characteristics and maternal education. Poverty only in the first year of life significantly increased the risk of asthma attacks and limiting long-standing illness in the fourth year of life among UK children; trends were in the expected direction in the QLSCD but did not reach statistical significance. Poverty in the fourth year of life only significantly increased the risk of all 3 outcomes for UK children but not for Quebec children. For children experiencing poverty in both the first and fourth years of life, the risks for all 3 outcomes also increased in the United Kingdom, whereas only the risk of limiting long-standing illness increased in Quebec. Adjustment for confounding had little effect on the increased risks associated with poverty. These findings suggest that experience of poverty at various times in early childhood increases the risk of asthma attacks and chronic illness in the fourth year of life; however, they also indicate that poverty at different stages of the early childhood life course may have different effects on chronic illness in different country settings.

Sustained Active Transportation is associated with a favorable body mass index trajectory across the early school years: Findings from the Quebec Longitudinal Study of Child Development birth cohort

Objective To determine the extent to which active transportation (AT) to and from school is associated with changes in body mass index (BMI) from kindergarten (6-year-olds) through grade 2 (8-year-olds). Methods The sample included 1170 children (50.4% of baseline participants) who were part of the Quebec Longitudinal Study of Child Development (QLSCD), a birth cohort established in 1998 in Quebec, Canada. Data were collected by trained interviewers using structured interviews and measuring height and weight in the home with the person most knowledgeable about the child's health. Relative weight was operationalized as age- and sex-adjusted BMI Z-scores. Results Growth curve analyses showed that using AT to and from school both when in kindergarten and in grade 1 was predictive of a lower BMI Z-score (coeff = - 0.18, SE = 0.09, p = 0.05) in grade 1. Using AT to and from school in kindergarten, grade 1, and grade 2 was predictive of a lower BMI Z-score (coeff = - 0.30, SE = 0.098, p = 0.003) in grade 2. No other covariates were predictive of relative weight across time, although having an overweight or obese mother was associated with a BMI Z-score of 0.39 (SE = 0.07, p < 0.001) across all time points. Conclusion Sustained AT is associated with more healthful trajectories of BMI across the early school years.

Duration of lack of money for basic needs and growth delay in the Quebec Longitudinal Study of Child Development birth cohort

To examine the relationship between duration of lack of money for basic needs and growth delay in a birth cohort. Mothers of children (n = 1929) from the Quebec Longitudinal Study of Child Development (QLSCD) participating when the children were ages 2(1/2) and 4 years were interviewed at home and data were extracted from birth records. Children's height at 4 years old was transformed into an age- and sex-adjusted z-score. A z-score under the 10th percentile of the Centers for Disease Control and Prevention population growth curve was equated with growth delay. Lack of money for basic needs (paying for rent, electricity and/or heating, clothing, medications or other needs) when the children were ages 2(1/2) and 4 years was reported by the mother. Only 2.5% of children experienced two episodes of lack of money for basic needs. Logistic regression analyses showed that, after adjusting for confounding variables, the probability of growth delay at 4 years among children whose families experienced two episodes of lack of money was higher than for their peers who had not lacked money (OR 3.43; 95% CI 1.54 to 7.66). Experiencing lack of money only at 2(1/2) years showed higher but not significant odds of growth delay at 4 years (OR 1.51; 95% CI 0.84 to 2.72), whereas the likelihood of growth delay was similar for children who experienced lack of money only at 4 years and for their counterparts who never lacked money (OR 0.74; 95% CI 0.26 to 2.11). In an industrialised country toddlers whose families experienced persistent lack of money for basic needs are more likely to have growth delay even after controlling for neonatal conditions and their mothers' characteristics.

Poverty and Cumulative Hospitalization in Infancy and Early Childhood in the Quebec Birth Cohort: A Puzzling Pattern of Association

We anticipate a negative gradient between income and hospitalization, since income is positively associated with good health. In a previous cross-sectional study, we reported an unexpected pattern of association between poverty and hospitalization for 5-month-old infants in Quebec. This study re-examines the poverty-hospitalization relationship within a longitudinal population study of the same birth cohort aged 3.5 years. Life table analysis, multivariable proportional hazard regression, and multivariable logistic regression were performed on data from the first four waves of the Quebec Longitudinal Study of Child Development (QLSCD). Probabilities of hospitalization were estimated by poverty status. The hazard ratios (HR) (Cox-regression) for duration of poverty (frequency of insufficient income) and severity of poverty (combining frequency and level of income insufficiency) were estimated, controlling for predisposing, enabling, and need determinants of hospitalization. At 3.5 years, 31% of children had been hospitalized at least once. Compared with children whose families had constantly sufficient income, children with intermittent poverty exhibited higher hospitalization risks (HR = 1.30; 95%CI = 1.04-1.64) while chronically poor children exhibited comparable hospitalization hazards (HR = 0.97; 95%CI = 0.73-1.27). Hospitalization risks for children in the severest poverty group resembled that of the non-poor group (HR = 0.99; 95%CI = 0.66-1.49), while children in less severely poor families were more likely to be hospitalized (HR = 1.26; 95%CI = 0.99-1.60). Results suggest hospitalization barriers for children living in chronic and severe poverty. If these barriers exist in a universal health care system, they may originate with primary care service organization or hospital care referral procedures.

Validación de escalas de seguridad alimentaria y de apoyo social en una población afro-colombiana: aplicación en el estudio de prevalencia del estado nutricional en niños de 6 a 18 meses

We conducted a cross-sectional study on 193 mothers of children 6 to 18 months of age in an African-Colombian community, with the objectives: (1) to adapt and validate the Community Childhood Hunger Identification Project scale, the DUKE-UNC-11 social support scale, and the Quebec Longitudinal Study of Child Development (QLSCD) partner support scale, and (2) to identify any existent relationship between nutritional status in infancy and both food insecurity and social support. We determined construct validity using factor analysis and theoretical models-based non-parametric correlations. Length-for-age and weight-for-length Z-results were calculated. Factor analyses reduced the hunger scale to one factor, the DUKE-UNC-11 scale to two factors, and the QLSCD scale to one factor. The Cronbach's alpha test ranged between 0.70 and 0.90. Both food insecurity and social support scales were correlated with mother's social conditions, and social support was positively associated with social networks and mother's self-perceived health status. Food insecurity, emotional-social support, and partner's negative support were associated with lower height-to-age and therefore a higher ratio of chronic malnutrition. The study supports the appropriateness of the instruments to measure the expressed concepts.