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The first 1000 days of life are a period of unique sensitivity and plasticity during which critical cognitive abilities are formed. Routine developmental screening tools aim to identify infants who would benefit from early intervention. While these tools have been validated for detecting children with more severe neurodevelopmental disorders, their ability to identify the larger proportion with below average cognitive function has not been sufficiently explored. The aim of this study was to examine the validity of the Ages and Stages Questionnaire (ASQ), for identifying children with later below average cognitive function.

The study population (n=8260) is formed from two national cohort studies, the Growing Up in Ireland (GUI) Infant cohort (n=7,444) and the Cork BASELINE cohort (n=816). The ASQ was completed at 8 months and 24-27 months respectively. Cognitive assessments were performed at age 5. Those scoring <1 standard deviation (SD) below the mean were categorised as below average cognitive function. Applying the currently used onward referral criterion (one fail in any domain) the sensitivity, specificity, positive and negative predictive values of the 8- and 24-27- month ASQ for detecting children with later below average cognitive function were calculated.

In the GUI cohort n=905 participants (12.5%) had scores <1SD below the mean on the Picture Similarities Scale. In the BASELINE cohort n=101 participants (13.4%) had an IQ <1SD below the cohort mean. Applying the currently used onward referral criterion (failing in any one domain in the ASQ), the sensitivity of the 8-month ASQ for detecting children scoring <1SD below the mean on the Picture Similarities Scale at age 5 was 16.4% (95% CI 14.0-19.0). The specificity was 92.0% (95% CI 91.3-92.6), with a positive predictive value (PPV) of 22.6% (95% CI 19.5-26.0) and a negative predictive value (NPV) of 88.5% (95% CI 87.7%-89.2%).

In the BASELINE cohort n=468 participants completed the 24-month ASQ and n=316 the 27-month ASQ. Applying the same onward referral criterion to the 24- and 27- month ASQ combined, the sensitivity for detecting those with an IQ <1SD below the cohort mean was 20.8% (95% CI 13.6-30.2) and the specificity was 91.1% (95% CI 88.6-93.2).

The ASQ has a low sensitivity for identifying children with below average cognitive function at age 5. The findings of this study suggest that if we are to intervene early in the developmental trajectory for children with below average cognitive function alternative methods of identifying high risk infants are needed.

Children with below average cognitive function represent a substantial yet under-researched population for whom academic and social demands, which increase in complexity year by year, pose significant challenge. Effects on emotional-behavioural development (EBD) are not well understood. The aim of this study was to compare trajectories of EBD for children with and without below average cognitive function. The underlying hypothesis was that trajectories of EBD would differ between groups, with divergence occurring as children are subject to increasingly complex cognitive demands.

Participants consist of 7,000 children and caregivers who completed the Growing Up in Ireland survey at age 3,5 and 9 years. Cognitive function was measured at age 3 using the Picture Similarities Scale. A t-score 1-2 standard deviations below the mean was categorised as below average cognitive function (n=767), and scores above this categorised as average cognitive function (n=6418). EBD was measured using the Strengths and Difficulties Questionnaire (SDQ) at age 3,5 and 9. Repeated measures ANOVA was used to examine the difference between the overall group means across the repeated measures of SDQ, the SDQ change over time, and the interaction between cognitive group and change over time. Further analysis of trajectories was performed using latent growth curve analysis.

Compared to those with average cognitive function, a significantly higher proportion of children with below average function were male (61.8% v 38.2%, χ2 (1, N=7134) = 42.07 p<0.001), born to a single parent family (22.4% v 14.7%, χ2 (1, N=7134) = 23.15 p<0.001), and had a parent who smoked (35.6% v 25.8%, χ2 (1, N=7134) = 33.23 p<0.001). Children with below average cognitive function had significantly higher mean total SDQ scores at all ages. Repeated measures ANOVA demonstrated a significant group-by-time interaction effect (F(2,7182)=4.649, p=0.010). The mean difference (MD) in SDQ between cognitive groups increased over time (MD Age 3:0.87, 95% confidence interval (CI) 0.53-1.21, Age 9 MD:1.49,95% CI 1.08-1.91). For those with average or above cognitive function the overall SDQ decreased between age 3-9 (MD: -0.49 95% CI -0.65—0.33). This decrease was not seen for those with below average function, who had a non-statistically significant increase in SDQ between age 3-9.

Children with below average cognitive function experience higher and worsening mean SDQ scores throughout childhood. A scalable method of early identification of children at risk for below average cognitive function should be a research priority for public health, enabling early intervention for cognitive and adaptive outcomes.

Parental incarceration (PI) is negatively associated with emotional, educational, and psychological child outcomes. However, few studies explore potential mechanisms through which these outcomes are transmitted or the means by which prosocial outcomes might develop. This study used data from two waves of a population cohort study of children aged 9 years and followed up aged 13 years living in Ireland. Children and parents (N = 8,568) completed measures of PI, primary caregiver (PCG) depression, PCG-child relationship quality, and child behavioral adjustment. We then conducted a secondary analysis on this national longitudinal study of children in Ireland. Using sequential mediation models, we observed a mediated indirect effect of PI on prosocial outcomes via PCG depression and PCG-child relationship quality. PI at age 9 was associated with increased difficulties and reduced prosocial behavior at age 13. Additionally, PI at age 9 affected PCG depression and the PCG-child relationship quality. Additionally, child prosocial outcomes, and emotional and behavioral difficulties were less apparent where PI had a weaker effect on PCG depression and the quality of PCG-child relationship. Supports that can mitigate the impact of PI for vulnerable caregivers and children are discussed.

Background
Parental incarceration (PI) is associated with adverse developmental outcomes for children affected. However, research in this area often reports conflicting results with few studies following children across time in non-U.S. populations. Additionally, more research is called for using multi-informant perspectives rather than relying on adult reports of child outcomes alone.

Methods
This study used data from the first two waves of a nationally representative cohort study of 8,568 children aged 9 years and followed up at age 13 living in the Republic of Ireland (2007–2012). Propensity score matching was used to match children who had experienced PI by the age of nine to children who had not experienced PI by sociodemographics and experience of other stressful events. Mental health, as measured by self-concept (Piers-Harris II) and externalizing and internalizing difficulties (strength and difficulties questionnaire), was compared across both groups.

Results
Fifty of the 8,568 children (weighted percentage 0.9%) reported experiencing PI by the age of nine. These children came from more socially disadvantaged homes and were more likely to have experienced other potentially stressful life events. In comparison to a matched sample of children not affected by PI, children affected by PI reported higher levels of anxiety at age nine. Longitudinal analysis indicated these children affected by PI also reported lower levels of happiness at age 13 with higher levels of emotional difficulties reported by their primary caregiver.

Conclusions
Children of incarcerated parents face a greater array of life challenges. PI had an association with child-reported levels of anxiety at age nine. PI also had a medium-term association on caregiver assessments of emotional difficulties of children affected as well child-reported levels of happiness over time.

Previous research has suggested that the children of teenage parents are at a high risk of developing both internalising and externalising behaviour disorders. The current study aimed to explore pathways through which children of teenage mothers show more externalising and internalising psychopathology than their peers whose parents were older. The present study used data from the first wave of the ‘Growing Up in Ireland’ 9-year-old cohort and employed structural equation modelling to assess the explanatory value of a model informed by previous research findings. Goodness-of-fit indices indicated that many aspects of the familial environment of Irish teenage families did indeed place children at a substantial risk of problematic developmental outcomes. In particular, the results implicated the influential power of economic stability and familial conflict on the well-being of teenage families and related child outcomes, results similar to those reported in international studies.

Keywords: teenage mothers in Ireland, economic stability, externalising problems, internalising problems

Objective
This study aims to examine the associations between prenatal exposure to maternal smoking, birth weight and persistent offspring psychiatric symptoms. Additionally, we aim to examine whether the relationship between prenatal maternal smoking and persistent offspring psychiatric symptoms is mediated by offspring birth weight.

Methods
This study used the Growing Up in Ireland (GUI) longitudinal cohort. The GUI is a nationally representative longitudinal study of children which consisted of three data collection waves, at ages 9, 13, and 17 years. Logistic regression analysis was used to examine associations between prenatal tobacco exposure, and offspring psychiatric symptoms. Linear regression was used to examine associations between prenatal tobacco exposure and offspring birth weight. We conducted a mediation analysis examining potential etiological pathways linking maternal smoking during pregnancy, offspring birth weight, and later offspring psychiatric symptoms. All analyses were adjusted for confounders including household income, maternal level of education, and family psychiatric history. Additionally, examination of birth weight and subsequent psychiatric symptoms also was controlled for prematurity.

Results
We found that the association between prenatal tobacco exposure and later psychiatric symptoms is mediated by birth weight.

Conclusions
This work provides further evidence that maternal smoking during pregnancy is an important modifiable lifestyle factor that has an impact not just on the physical health of offspring but also their mental wellbeing. Supporting women with structured smoking cessation programs at the earliest stages of pregnancy should be a public health priority.

Aims
This study aims to replicate Przybylski and Weinstein (Psychol Sci 28(2):204–215, 2017), using a large population cohort to examine the validity of the proposed Goldilocks Hypothesis, which states that moderate digital media engagement may be beneficial and that both high and low usage may have a negative relationship with mental wellbeing.

Methods
Using the GUI98 cohort, we used separate weekday and weekend time-based categorical variables indicating time spent online, playing video games, watching TV/films as well as a frequency variable indicating multiscreening, and their associations with SDQ internalizing and externalizing symptoms using linear and quadratic regression parameters. We followed procedures for confounder adjustments outlined in Przybylski and Weinstein (Psychol Sci 28(2):204–215, 2017).

Results
As hypothesized by the Goldilocks Hypothesis, time spent online watching TV/films at the weekend and multiscreening all had curvilinear relationships with internalizing and externalizing symptoms with significantly higher symptoms for no time as well as for higher exposures. internalizing and externalizing symptoms increased with time spent playing video games.

Conclusions
This brief report supports the Goldilocks Hypothesis, that suggests that moderate use of digital technology is not intrinsically harmful and may instead be beneficial, even necessary in a world becoming ever more increasingly reliant on digital media (Przybylski and Weinstein in Psychol Sci 28(2):204–215, 2017).

Objectives
To assess the impact of digital media usage on psychiatric symptoms in an adolescent population utilizing a longitudinal cohort design.

Methods
Using two waves of the GUI child cohort, age 13 (N = 7527) and age 17/18 (N = 6126), we used latent class analysis (LCA) to create latent groups centred around self-reported time spent online, and the self-reported behaviours children engaged with online. At both waves, the 4 class latent model suited best. We used the different symptoms scales of the Strengths and Difficulties Questionnaires (SDQ), self-reported, at age 17 as our outcome variable. Using linear regression analysis, we then examined the associations between our latent class model and psychiatric symptoms, using moderate usage as our reference group, with adjustments being made for baseline psychiatric symptoms, maternal education and pre-diagnosed mental disorder.

Results
For females, placement in the high usage group at 13 was associated with increased internalizing symptoms, whereas placement in the high usage group at 17 was associated with an increase in all symptoms. For males, placement in the high usage group at 17 was associated with increased emotional symptoms, and placement in the “low usage & behaviour engagement”group, a group showing low reported time online and low engagement in our measured online behaviours at 17, was associated with an increase in all symptoms. Finally for both sexes, placement in the “moderate usage, entertainment only” group at age 13, (a group reporting no school-based online engagement), was associated with increases in all symptoms except emotional symptoms.

Conclusion
High digital media usage is associated with increased psychiatric symptoms in both males and females, with moderate usage associated with positive effects on symptoms compared to both our high usage, and low usage groups.

Keywords
Digital engagement, Psychiatric symptoms, Internet usage, Latent class analysis

The incidence of adiposity in the early years of life has outgrown the prevalence in older children and adolescents globally; however, the factors influencing weight gain are predominantly studied in adults. This study examines the relationship between changing economic conditions during the Irish recession and child weight in a nationally representative sample of 10,011 Irish children studied at 9 months, 3 years and 5 years old. This study is the first to use longitudinal anthropometric measurements to estimate the impact of direct parental unemployment on children’s weight. Fixed effect logistic regression is used to examine the effects of parental unemployment on weight using the Growing up in Ireland infant cohort from 2008 to 2013. Weight and length/height measured by trained interviewers and child growth charts are used to quantify children’s weight status according to BMI-for-age and weight-for-age measures. For BMI-for-age, the probability of a child being classified as overweight/obese is 8 percentage points higher if either parent experiences unemployment. A sensitivity analysis of weight-for-age indicates that the probability is of similar magnitude across several alternative growth charts and definitions of adiposity (the WHO standard, British Growth Reference, and Centers for Disease Control). The analysis is repeated, cross-sectionally, for physical activity and diet to clarify mechanisms of effect. The probability of a child consuming healthy food and physical activity with an implied cost is lower if either parent becomes unemployed. A focus on overweight/obesity in the early years is of crucial importance as if current trends are not addressed, a generation of children may grow up with a higher level of chronic disease.