External Publications Using GUI Data

Children born preterm have poorer outcomes than children born full-term, but the caregiving environment can ameliorate some of these differences. Recent research has proposed that preterm birth may be a plasticity factor, leading to better outcomes for preterm than full-term infants in higher quality environments. This analysis uses data from two waves of an Irish study of children (at 9 months and 3 years of age, n = 11,134 children) and their caregivers (n = 11,132 mothers, n = 9998 fathers) to investigate differences in how caregiving affects social, cognitive, and motor skills between full-term, late preterm, and very preterm children. Results indicate that parental emotional distress and quality of attachment are important for child outcomes. Both being born very preterm and late preterm continue to be risk factors for poorer outcomes at 3 years of age. Only fathers’ emotional distress significantly moderated the effect of prematurity on infants’ cognitive and social outcomes—no other interactions between prematurity and environment were significant. These interactions were somewhat in line with diathesis stress, but the effect sizes were too small to provide strong support for this model. There is no evidence that preterm birth is a plasticity factor.

Background:
Regulatory problems in infancy are associated with internalizing and externalizing symptom trajectories across childhood. It is unknown whether early screen media exposure exacerbates the association between infant regulatory problems and childhood internalizing and externalizing symptom trajectories.

Methods:
We studied 10,170 individuals from the Growing Up in Ireland ’08 cohort. Parents reported on their children’s regulatory problems at 9 months, screen media exposure at 3 years, and internalizing and externalizing symptoms at 3, 5, 7, and 9 years. Children were categorized based on their patterns of co-developing internalizing and externalizing symptoms using parallel process latent class growth analysis. Subsequently, multinominal logistic regression analyses were conducted to estimate whether screen media exposure (>1 hour or >2 hours) moderated the association between regulatory problems in infancy and co-developing internalizing and externalizing symptom classes across childhood.

Results:
There were four groups of children with distinct patterns of co-developing internalizing and externalizing symptoms: 1) low stable internalizing and low decreasing externalizing symptoms (N= 6236; 61.3%); 2) low stable internalizing and moderate stable externalizing symptoms (N= 2029; 20%); 3) moderate increasing internalizing and moderate decreasing externalizing symptoms (N= 1263; 12.4%); 4) moderate increasing internalizing and high increasing externalizing symptoms (N= 642; 6.3%). Presence of regulatory problems at 9 months and excessive screen media exposure at 3 years (particularly >2 hours) were independently associated with increased likelihood of all classes. Excessive screen media exposure at 3 years did not significantly moderate the association between regulatory problems at 9 months and internalizing and externalizing symptom trajectories.

Conclusions:
Both regulatory problems in infancy and screen media exposure >2 hours in early childhood are early risk factors for the development of internalizing and externalizing symptoms. However, the association between infant regulatory problems and childhood internalizing and externalizing symptoms appears to operate independently of excessive screen media exposure. Clinicians should be aware of, and treat, regulatory problems in infancy to prevent chronic patterns of self-regulatory problems across childhood. Further, they should discuss and advocate for family media plans with parents to help decrease the long-term negative effects on internalizing and externalizing symptoms.

Introduction
Compared to their more affluent peers, children of low socioeconomic position (SEP) are more likely to experience poor mental health. Correctly identifying factors that influence internalising and externalising symptoms is imperative for early, targeted intervention. Distinguishing between symptoms that are transient and chronic, and singular or co-morbid is important. We investigated how internalising and externalising behaviours co-occur in children from childhood to adolescence, and examined the association between these behaviours and childhood family- and child-level risk factors – including maternal characteristics, economic strain and experiences in childhood.

Method
Using the large, nationally representative, longitudinal sample from the Growing Up in Ireland study, two mixture modelling techniques were applied: Latent Class Analysis to unveil multidimensional family profiles by clustering subjects with similar familial, maternal and lived experiences, and Group-Based Multi-Trajectory Model to identify joint behavioural trajectories based on responses to the internalising and externalising subscales of the Strength and Difficulty Questionnaire, measured at three time points (age 9, 13 and 17).

Outcome
Half of the children (51%) showed no behavioural problems, however a large proportion of children experienced substantial economic strain while growing up in Ireland during the 2000s. Worse SEP conditions were linked to less advantageous maternal characteristics, e.g. mothers who were young, smoked and did not breastfeed. A clear gradient of troubled behaviour was seen as socio-economic difficulties increased. Changes in family profiles were associated with minor or modest alterations in behavioural outcomes. Implications for policy are discussed.

Technological advancement has seen a rise in computer-based and online gaming, and the online space has facilitated a proliferation in gambling options that increasingly adopt game-like features. There is a concern that gaming in childhood could predispose subsequent engagement with gambling behaviors, which has drawn the attention of parents, researchers, governments, and the European Union. To inform policy and legislation aimed at mitigating gambling-related harms, this research uses three waves of longitudinal data from Ireland to examine whether computer game engagement at 9-years-old (collected in 2007/8), and online gaming at 17 and 20, is associated with gambling participation in young adulthood. Multiple regression models, adjusting for a range of socio-economic and health characteristics, revealed that online gaming at 17 was associated with 1.4 higher odds of more frequent online gambling at 20 years (p = 0.011), while online gaming at 20 was associated with a 1.7 higher odds (p < 0.001). However, no association between early computer-based gaming at 9 years and subsequent gambling behaviors at 20 was uncovered for this cohort (born in 1998). Given more recent introductions of loot boxes and social casino games, continuous research is needed for future cohorts which may be greater affected by such developments.

Digital technologies have become an increasingly prominent feature of children’s lives both within and outside educational environments (McCoy, Quail, and Smyth 2012. Influences on 9-Year-Olds’ Learning: Home, School and Community. Dublin: Department of Children and Youth Affairs). Despite considerable media debate, we have little robust evidence on the impact of technology use on children’s development, both academically and socially. Much of the literature in this area relies on small-scale cross-sectional studies. Using longitudinal data on 8500 9-year-old children in Ireland, we examine the influence of early mobile phone ownership on children’s performance in reading and maths between 9 and 13 years of age. Across both reading and maths domains, children who already report owning a phone by the age of nine fare less well in terms of their academic development as they move into adolescence. The measured effects are sizeable, implying about 4 percentile lower ranking on standardised tests for an average student. Our results are consistent with the idea that there may be significant educational costs arising from early mobile phone use by children. Parents and policymakers should consider whether the benefits of phone availability for children are sufficiently large to justify such costs. We suggest a range of direct and indirect cognitive effects that could help explain these results.

KEYWORDS: Mobile phone ownership; child development; academic outcomes; early owners; longitudinal data

The increasing importance of identifying lesbian, gay, bisexual and transgender (LGBT+) populations is a key driver in changes to demographic data collection in representative surveys of youth. While such population-based data are rare, Growing Up in Ireland (GUI), an Irish, government-funded, longitudinal survey, includes sexual orientation and gender identity (SOGI) measurements. This qualitative study responds to a query from the GUI study team and aims to identify how best to collect SOGI data in future waves of GUI. A university Human Research Ethics Committee granted approval for online consultations with LGBT+ youth (n = 6) with experiential expertise in policy making. The research is underpinned by rights-based public patient involvement (PPI) with recorded discussions, which were transcribed and imported into NVivo 12, generating the theme “recognition in research, policy and society”. This co-created article, with the LGBT+ young PPI Panel members, commends the inclusion of SOGI data in GUI and recommends changes in question placement and phrasing. Aligning with best practice, the PPI members provide a template for wording on consecutive sex and gender questions, expanded sexual orientation identity categories and maintaining the existing well-phrased transgender question from GUI. This offers potential to improve the quality of the SOGI data collected and the experience of those completing the questionnaire. These findings extend beyond GUI, with relevance for surveys with youth populations. This paper underscores the potential and benefits of participatory approaches to research with youth and views their role beyond simply as sources of data.

Keywords: LGBT+, sexual minority youth (SMY), gender minority youth (GMY), Growing Up in Ireland (GUI), SOGI measurement, quantitative, qualitative, survey design, PPI

Objective
To explore whether the associations between developmental delays in the first year of life and psychosocial outcomes in preschool children are affected by participation in organized sport.

Study design
Data were obtained from the infant cohort of the Growing Up in Ireland project. Parents reported on child development (Ages and Stages Questionnaire) at age 1 year, psychosocial characteristics (Strengths and Difficulties Questionnaire) at ages 3 and 5 years, and engagement in organized sport at age 5 years. Data were analyzed using mixed models.

Results
At age 1 year, 15% of the cohort was classified as having developmental delays. These children exhibited more behavioral difficulties (0.55, ±0.27; mean difference, ±95% confidence limits [CL]) (P < .0001) and fewer prosocial behaviors (−0.54, ±0.11) (P < .0001) at age 3 years. For boys in this group, engagement in sport was associated with a significant decrease in behavioral difficulties between ages 3 and 5 years (−0.44, ±0.39) (P = .03). Compared with those classified as lacking regular engagement (ie, never engaging, or engaging <1 hour/week), the relative effect of sport on changes in behavioral difficulties for boys with developmental delays was statistically significant (0.70, ±0.59) (P = .02). Participation in sport was not associated with significant changes in behavioral difficulties for girls, or a significant change in prosocial behaviors for boys or girls.

Conclusions
Regular participation in sport by boys could attenuate some of the behavioral difficulties associated with early development. Lack of opportunities for engaging in sport could negatively affect boys’ behavioral regulation in the preschool period.

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.

Little is known about the link between childhood and adolescent mental health (MH) difficulties and political outcomes in adulthood. This represents an important knowledge gap in understanding early individual-level factors for future political outcomes. Using the Growing up in Ireland cohort, which follows 8568 children from 9 to 20 years, we examine how different MH difficulties, and their co-occurrence, are associated with various political outcomes. The results show childhood/adolescent MH difficulties are important predictors of political outcomes at age 20. Adolescents with chronic co-occurring MH difficulties starting in childhood report a lower interest in politics, lower trust in politicians, are less likely to register to vote, but if voting, are more likely to vote for an antiestablishment party. Adolescents with chronic emotional MH difficulties starting in childhood also report lower trust in politicians, are less likely to register to vote, and report a higher likelihood of voting for an antiestablishment party when voting. Additionally, they evidence lower levels of external political efficacy.

Background
Past empirical evidence on the longitudinal relations between emotional mental health symptoms and parent-child close relationships has produced mixed and inconclusive results. Some studies suggest a unidirectional relation, whereas other studies point toward a bidirectional association. Additionally, most of the past research has been carried out with adolescent samples, rather than children. Hence, this study aimed to estimate the longitudinal relations between children’s trait emotional difficulties and trait parent-child closeness, accounting for the time-invariant and time-varying state components of each factor.

Methods
Participants were 7,507 children (ages 3 years, 5 years, 7 years, and 9 years) from the Growing Up in Ireland cohort. Α bivariate stable trait, autoregressive trait, and state (STARTS) model was estimated using Bayesian structural equation modelling.

Results
The STARTS model revealed that children’s emotional difficulties and parent-child closeness were relatively stable across time, and these overarching traits were strongly negatively correlated. Children’s earlier trait emotional difficulties predicted later trait parent-child closeness and vice versa between 3 years and 5 years, and between 5 years and 7 years, but these effects disappeared between 7 years and 9 years. At all pairs of time points, state emotional difficulties and state parent-child closeness were weakly negatively correlated.

Conclusions
Overall, the results suggest that early and middle childhood are critical stages for improving parent-child relationships and reducing children’s emotional difficulties. Developing close parent-child relationships in childhood appears to be a key factor in reducing children’s subsequent emotional difficulties. Children who face greater than usual emotional difficulties tend to be more withdrawn and less receptive to close parent-child relationships and this could serve as an important screening indicator.

Purpose
This study examines the expressive language and speech of twins, relative to singletons, at 3 and 5 years, with the aim of determining if a twinning effect occurs during this developmental period. The possibility of twins outgrowing a twinning effect was investigated.

Method
A weighted population-based sample of 185 twins and 1,309 closely spaced singletons who participated in the Growing Up in Ireland study was analyzed. Their development was compared using a standardized expressive vocabulary assessment and parent interview at 3 and 5 years as well as teacher reports at 5 years. Causal steps mediation analyses were subsequently conducted to determine if gestation and birth weight mediated twin–singleton differences in expressive vocabulary development.

Results
Twins’ expressive vocabulary scores were slightly lower than those of singletons at 3 years, but there was no significant difference at 5 years. More parents of twins reported “a little” concern about their child’s expressive language and speech skills at 3 years, although there was no significant twin–singleton difference 2 years later. Teachers’ ratings of twins’ and singletons’ expressive language and speech skills at 5 years were comparable. Shorter gestations and lower birth weights mediated twins’ lower expressive vocabulary scores at 3 years.

Conclusions
A very small twinning effect on expressive vocabulary development exists at 3 years and is outgrown by 5 years. Twins born after shorter gestations or at a lower birth weight are at an increased risk of having less developed expressive vocabulary skills at 3 years.

Using the first wave of the Growing Up in Ireland Survey of nine year old children we examine whether a teacher’s assessment of their pupil’s academic ability is influenced by the weight status of the child and/or the child’s mother. Multivariate regression analyses of the teacher’s assessment, controlling for the child’s actual test performance, their BMI, their mother’s BMI, other socio-demographic and teacher characteristics were undertaken. The study highlighted that child BMI was not a significant determinant but that children whose mother was obese were more likely to be rated as below average in reading and in maths compared to those whose mother was leaner, after adjusting for their measured ability. The potential for mother’s weight status to influence teachers’ assessments of their children’s perceived ability could have long term ramifications for educational outcomes and warrants further study.

Background
Social inequalities in the prevalence of childhood overweight and obesity are well-established, but less is known about when the social gradient first emerges and how it evolves across childhood and adolescence.

Objective
This study examines maternal education differentials in children’s body mass trajectories in infancy, childhood and adolescence using data from four contemporary European child cohorts.

Methods
Prospective data on children’s body mass index (BMI) were obtained from four cohort studies—Generation XXI (G21—Portugal), Growing Up in Ireland (GUI) infant and child cohorts, and the Millennium Cohort Study (MCS—UK)—involving a total sample of 41,399 children and 120,140 observations. Children’s BMI trajectories were modelled by maternal education level using mixed-effect models.

Results
Maternal educational inequalities in children’s BMI were evident as early as three years of age. Children from lower maternal educational backgrounds were characterised by accelerated BMI growth, and the extent of the disparity was such that boys from primary-educated backgrounds measured 0.42 kg/m2 (95% CI 0.24, 0.60) heavier at 7 years of age in G21, 0.90 kg/m2(95% CI 0.60, 1.19) heavier at 13 years of age in GUI and 0.75 kg/m2 (95% CI 0.52, 0.97) heavier in MCS at 14 years of age. The corresponding figures for girls were 0.71 kg/m2 (95% CI 0.50, 0.91), 1.31 kg/m2 (95% CI 1.00, 1.62) and 0.76 kg/m2 (95% CI 0.53, 1.00) in G21, GUI and MCS, respectively.

Conclusions
Maternal education is a strong predictor of BMI across European nations. Socio-economic differentials emerge early and widen across childhood, highlighting the need for early intervention.

Objective
This paper examines the joint impact of maternal employment and childcare during infancy on childhood weight at ages three and five in the context of weak social support for early childhood care and education.

Method
Using three waves of longitudinal data from the Growing-Up in Ireland survey (n = 8,393 age three, n = 8,039 age five), propensity score matching is used to address the endogeneity of employment and childcare decisions. Selection on observables is used to assess potential bias arising from selection on unobservables whereby unobserved characteristics of the mother or child may jointly influence child weight and maternal employment and childcare.

Results
Full-time maternal employment at nine months combined with either formal or informal childcare increases the likelihood of being overweight at three years by 8.1% and 5.9% respectively, but only for children of highly educated mothers. Similar results are observed for part-time employment coupled with informal (7.5%) or parental (8.0%) care. The results for mothers with lower levels of education are either not significant or favourable. While the majority of the effects dissipate by age five, there is some evidence that full-time maternal employment coupled with informal care increases the risk of being overweight at both ages three and five for children of higher-educated mothers. An assessment of selection bias finds that the estimates of full-time employment combined with formal childcare by well-educated mothers are a lower bound, such that the true effect on child weight may be understated.

Conclusions
The findings for Ireland are consistent with studies from the United States and the United Kingdom, and are in contrast to findings from the rest of Europe, suggesting the role of institutional factors, such as the lack of subsidised, universal, high-quality childcare.

This paper examines the relationship between maternal employment, childcare during infancy and the overweight status of pre-school children. Using data from the Infant Cohort of the Growing-Up in Ireland Survey, propensity score matching addresses the issue of potential selection bias, quantile regression allows the impact of both maternal employment and childcare to be examined throughout the weight distribution and multiple imputation is used to address the problem of missing data due to item non-response. The results suggest that both full-time and part-time maternal employment when a child is 9 months old increase the likelihood of being overweight at 3 years old, but only for children of mothers with higher levels of education. Informal childcare at 9 months also has harmful effects on child weight, but again only for children of more educated mothers. Quantile regression finds that the children most impacted by maternal employment are those at the upper percentiles of the weight distribution. When selection on observables is used to assess bias arising from selection on unobservables, maternal employment estimates are determined to be a lower bound, while informal childcare results could be attributed to selection bias. Overall findings are consistent with research from North America and the United Kingdom, and are in contrast to recent findings from the rest of Europe, suggesting the possible role of institutional factors.

Background
Parental obesity is a predominant risk factor for childhood obesity. Family factors including socio-economic status (SES) play a role in determining parent weight. It is essential to unpick how shared family factors impact on child weight. This study aims to investigate the association between measured parent weight status, familial socio-economic factors and the risk of childhood obesity at age 9.

Methodology/Principal Findings
Cross sectional analysis of the first wave (2008) of the Growing Up in Ireland (GUI) study. GUI is a nationally representative study of 9-year-old children (N = 8,568). Schools were selected from the national total (response rate 82%) and age eligible children (response rate 57%) were invited to participate. Children and their parents had height and weight measurements taken using standard methods. Data were reweighted to account for the sampling design. Childhood overweight and obesity prevalence were calculated using International Obesity Taskforce definitions. Multinomial logistic regression examined the association between parent weight status, indicators of SES and child weight. Overall, 25% of children were either overweight (19.3%) or obese (6.6%). Parental obesity was a significant predictor of child obesity. Of children with normal weight parents, 14.4% were overweight or obese whereas 46.2% of children with obese parents were overweight or obese. Maternal education and household class were more consistently associated with a child being in a higher body mass index category than household income. Adjusted regression indicated that female gender, one parent family type, lower maternal education, lower household class and a heavier parent weight status significantly increased the odds of childhood obesity.

Conclusions/Significance
Parental weight appears to be the most influential factor driving the childhood obesity epidemic in Ireland and is an independent predictor of child obesity across SES groups. Due to the high prevalence of obesity in parents and children, population based interventions are required.