External Publications Using GUI Data

This article investigates the dynamics of the gender pay gap using an administrative dataset of Irish graduate earnings. Although male and female graduates have similar earnings initially, a substantial gap emerges in the 10 years after graduation. We focus on three possible sources: childbirth, field of study, and job mobility. We find that the gap is driven by the earnings of mothers, which fall by 24 per cent relative to trend immediately after childbirth and this effect is evident for all field groupings. We examine and dismiss the possibility that the gender difference is driven by job mobility; in fact, almost all the difference arises for job stayers. Although there is a large and persistent reduction in average hours of work after childbirth, this does not seem to explain all of the emerging gap. Our results suggest that policy measures should focus on earnings dynamics within firms.

Keywords: gender pay gap; motherhood penalty; field of study.

Background
Tobacco use is closely linked to social and health inequalities, including economic vulnerability, morbidity, and premature death. Young adults with disabilities experience significant social and material hardships, which may be exacerbated by tobacco use. Limited research exists on smoking and e-cigarette use in this population. This study examines the prevalence of disability among young adults in Ireland, compares smoking and e-cigarette use between those with and without disabilities, identifies protective and risk factors, explores shared risk factors, and evaluates disability as an independent risk factor for smoking and e-cigarette use.

Methods
We analysed weighted data from 4,729 20-year-olds in the Growing Up in Ireland Cohort ’98 study who were present in Waves 1 (2008), 3 (2016), and 4 (2019). Current smoking, e-cigarette use, disability (excluding mental ill-health) and all other variables were assessed at Wave 4, while peer smoking data were drawn from Wave 3. Analyses were conducted using SPSS version 27.

Results
18.1% of participants reported a disability, which was associated with significantly higher smoking (41.8% vs. 36.7%) and e-cigarette use (16.1% vs. 12.9%). Protective factors against both behaviours included being female (OR 0.87 for smoking, OR 0.57 for e-cigarettes), later smoking initiation (OR 0.35, OR 0.62), living in two-parent families (OR 0.83, OR 0.70), and physical activity (smoking only). Risk factors included having peers who smoked (OR 3.67 for smoking; OR 2.36 for e-cigarette use) and caregivers who smoked (OR 1.48, OR 1.48), being employed at age 20 (OR 1.58, OR 1.48), and social media engagement (smoking only). Young adults with disabilities were significantly more likely to experience risk factors (e.g., earlier smoking initiation, caregivers who smoked, one-parent families, employment) but were less likely to have peers who smoked or engage with social media. Disability was independently associated with a higher likelihood of smoking (by 54%) and e-cigarette use (by 36%) after adjusting for protective and risk factors.

Conclusion
Higher smoking and e-cigarette use in 20-year-olds with disabilities adds further inequality to their lives. Increased awareness, targeted surveys and focused prevention and therapeutic interventions are required to reduce inequalities in this population and hasten the tobacco endgame.

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.

The experience of sexual intercourse for the first time is a significant life event, and influenced by a range of individual, cultural and societal factors. Age of first sexual initiation is a major area of policy and research focus, as the circumstances of first sex (e.g. whether contraception was used, whether it was perceived to have occurred ‘at the right time’), and the consequences of first sex for later outcomes (e.g. diagnoses of sexually transmitted infections (STIs), early parenthood), have important implications for health and wellbeing. In this report, we use data from the ’98 Cohort of Growing Up in Ireland (GUI), the national longitudinal study of children and young people in Ireland, to examine the factors associated with age of sexual initiation among young adults, and the way in which age of first sex influences the circumstances of first sex and selected outcomes. Age and circumstances of first sex, and selected outcomes, are all based on data collected during the fourth wave of data collection for the ’98 Cohort of GUI, when the young people were 20 years of age.

BACKGROUND
Early studies show that children might be ‘resilient’ when families navigate economic crises and related job loss. What resilience means is unclear, though, and why and from whom resilience is required has seldom been examined.

OBJECTIVE
I theorise children’s prosociality – helping, supporting and comforting others – as a form of transformative resilience. From a social reproduction perspective, I also consider how prosociality imbues and is influenced by caregiving relationships within families. I examine how children’s prosociality/caregiving (unpaid labour) developed in response to parents losing and regaining employment (paid labour) amid the Great Recession in Ireland.

METHOD
I rely on cohort data from children’s early years to adolescence (Growing Up in Ireland, 2008-2022). I estimate growth-curve and OLS models for prosocial development and outcomes tapping into paid and unpaid labour. Associations with parental job loss are identified net of observables while outlining conditions for causal claims. FINDINGS Children whose mothers experienced job loss are rated more prosocial than their peers from middle childhood onwards. Girls with younger siblings drive this finding. At age 13, the same group is more likely to provide regular care within the household, while their mothers scale back caregiving and reprise paid work after heightened childcare responsibilities during the crisis.

CONTRIBUTION
The study contributes to debates on the formation of prosociality, the intergenerational consequences of job loss, and the household division of labour among adults and children. Findings suggest focusing on if and how families cope with a context unequally structured by (labour) markets and gender norms.

Background
At age 5, while only embarking on their educational journey, substantial differences in children’s cognitive ability will already exist. The aim of this study was to examine the causal association between below average cognitive ability at age 5 years and child-reported experience of school and self-concept, and teacher-reported class engagement and emotional-behavioural function at age 9 years.

Methods
This longitudinal cohort study used data from 7,392 children in the Growing Up in Ireland Infant Cohort, who had completed the Picture Similarities and Naming Vocabulary subtests of the British Abilities Scales at age 5. Principal components analysis was used to produce a composite general cognitive ability score for each child. Children with a general cognitive ability score more than 1 standard deviation (SD) below the mean at age 5 were categorised as ‘Below Average Cognitive Ability’ (BACA), and those scoring above this as ‘Typical Cognitive Development’ (TCD). The outcomes of interest, measured at age 9, were child-reported experience of school, child’s self-concept, teacher-reported class engagement, and teacher-reported emotional behavioural function. Binary and multinomial logistic regression models were used to examine the association between BACA and these outcomes.

Results
Compared to those with TCD, those with BACA had significantly higher odds of never liking school [Adjusted odds ratio (AOR) 1.82, 95% CI 1.37–2.43, p < 0.001], of being picked on (AOR 1.27, 95% CI 1.09–1.48) and of picking on others (AOR 1.53, 95% CI 1.27–1.84). They had significantly higher odds of experiencing low self-concept (AOR 1.20, 95% CI 1.02–1.42) and emotional-behavioural difficulties (AOR 1.34, 95% CI 1.10–1.63, p = 0.003). Compared to those with TCD, children with BACA had significantly higher odds of hardly ever or never being interested, motivated and excited to learn (AOR 2.29, 95% CI 1.70–3.10).

Conclusion
Children with BACA at school-entry had significantly higher odds of reporting a negative school experience and low self-concept at age 9. They had significantly higher odds of having teacher-reported poor class engagement and problematic emotional-behavioural function at age 9. The findings of this study suggest BACA has a causal role in these adverse outcomes. Early childhood policy and intervention design should be cognisant of the important role of cognitive ability in school and childhood outcomes.

Bullying can occur at all ages and has been associated with several negative impacts on the psychological and emotional well-being of victims. While the transition to adulthood may be an opportunity for victims to escape bullying, prior research has suggested some continuity of victimisation experiences into adulthood. However, research on victimisation among young adults remains scarce and no prior study has examined this issue in the Irish context. Binary logistic regression was used to examine the likelihood of victimisation at age 20 based on the respondent’s prior victimisation history and other risk factors, using data from 4693 respondents in the Growing Up in Ireland National Longitudinal Study at age 9, 13, 17 and 20. Moreover, the risk of depression and levels of global self-esteem at age 20 were examined in terms of (long-term) victimisation experiences. Respondents who were previously victimised in adolescence and respondents who were chronically victimised in childhood and adolescence were approximately 3.5 and 4 times more likely to be victimised at age 20 respectively than respondents who were never victimised. The negative outcomes of victimisation regarding the risk of depression and lower levels of self-esteem were more severe for respondents who experienced more persistent prior victimisation. In conclusion, more persistent long-term victimisation experiences are associated with more severe negative outcomes and an increased risk of continued victimisation throughout the transition to adulthood compared to less persistent or no prior victimisation. Therefore, supporting affected individuals to escape victimisation as early as possible is crucial.

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.

Background
Early and risky adolescent alcohol use have each been associated with adult alcohol consumption. However, it remains unclear whether these behaviours independently predict later-life substance use when considered jointly, and research examining links with substances other than alcohol is limited. This study addresses these gaps by examining longitudinal associations between age at first alcohol and risky adolescent alcohol use, with alcohol, tobacco, cannabis and other drug use in early adulthood, and aims to identify critical periods for public health interventions.

Methods
Growing Up in Ireland is a nationally representative cohort (recruited aged 9 [Wave 1], born 1997–1998). Survey-weighted logistic regression examined whether age at first alcoholic drink and risky alcohol use at age 17 (Alcohol Use Disorders Identification Test scores) independently predict high-risk alcohol (AUDIT > 15), tobacco, cannabis and other drug use at age 20. Models were adjusted for age, sex, academic ability, personality, psychological factors, socioeconomic status, familial, peer and neighbourhood substance use.

Results
The study included 4554 participants (49.8% female). Early alcohol use was common, with 27% reporting use aged 14 or younger. By age 20, 14% reported high-risk alcohol, 38% tobacco, 24% cannabis and 28% other drug use. Older age at first alcohol was associated with dose-response reductions in the odds of high-risk alcohol, tobacco, cannabis and other drug use at age 20, relative to those initiating alcohol at 14 or younger. Adolescents with high-risk alcohol use had double the odds of tobacco (adjusted odds ratio (aOR) 2.1, 95% confidence intervals (CI) 1.3–3.30) and other drug use (aOR 2.5, 95% CI 1.6–4.1) and an 11-fold increase in the odds of continued high-risk alcohol use (aOR 11.5, 95% CI 7.0–18.6) at age 20, relative to adolescents with low-risk alcohol use.

Conclusions
Age at first alcohol and risky adolescent alcohol use independently predict substance use in early adulthood when considered jointly in extensively adjusted models. These findings highlight the continued urgent need for public health interventions that address factors associated with early alcohol use and support adolescents who use alcohol in a high-risk manner given their elevated risk of progression to more serious substance use as adults.

Background
Whether, and how, infant characteristics and parenting quality interact is one of developmental psychology’s key questions. However, whether specific interaction patterns replicate across cohorts or developmental outcomes is largely unknown. This study investigates whether infant characteristics and parenting quality are independent predictors (additive effects) of child outcomes or interact such that certain infants particularly suffer from poor parenting (diathesis stress), particularly benefit from good parenting (vantage sensitivity) or both (differential susceptibility).

Methods
Individual participant data from over 30,000 children from four prospective cohorts were pooled. Using a competitive-confirmatory approach of model evaluation, 16 possible permutations of infant characteristics (temperament and birthweight), parenting (maternal-reported stimulating and sensitive parenting) and later developmental outcomes (fluid and crystalised intelligence, internalising and externalising behaviour) were tested. The robustness of results was evaluated by subsequently varying analytic methods, using alternative parenting measures including observer reports and excluding covariates.

Results
AIC values in 10/16 analyses indicated infant characteristics acted independently of maternal-reported parenting for predicting developmental outcomes. Interaction patterns indicating diathesis stress (4/16), vantage sensitivity (2/16) or differential susceptibility (0/16) were rare or absent. However, diathesis-stress patterns were frequently found regarding birthweight and internalising behaviours, which were largely robust to methodological changes.

Conclusions
Developmental outcomes are more consistently explained by additive effects rather than by interaction effects.

This study uses high-quality longitudinal data from the Growing Up in Ireland study to examine the interplay between home learning environment (HLE) and early childhood education (ECE) in explaining children’s skills development from 9 months to 5 years old across parental socioeconomic status (SES). Random-effects linear regression models show that: (1) supportive HLE improves children’s cognitive and socioemotional skills and ECE quality critically fosters early socioemotional skills; (2) SES is associated with higher early cognitive and socioemotional outcomes, while responsive and consistent parenting behaviours among low-SES parents is particularly critical to improve their children’s socioemotional well-being; (3) high-quality ECE attendance compensates for children’s behavioural problems in less responsive parenting environments, especially among low-SES families, whereas home literacy stimulation is necessary condition for high-quality ECE attendance to benefit children’s early cognitive skills. Overall, HLE and ECE mutually interact in explaining differences in children’s early skills development across SES groups.

Purpose
Despite growing concerns about trends in cocaine use, there is a shortage of longitudinal research that prospectively examines risk and protective factors associated with cocaine initiation and use in general youth populations. This study addresses this gap.

Methods
Growing Up in Ireland is a nationally representative cohort. Individual, family, and socio-environmental exposures associated with incident past-year cocaine use at ages 17 (N = 5965) and 20 (n = 4549) were assessed with survey-weighted logistic regression using generalised estimating equations. Prevalent past-year cocaine use at 20 (N = 4679) was analysed using generalised estimating equations complemented by gradient-boosted decision trees and Shapley explanations.

Results
221 (3.7%) self-reported cocaine use at 17 and 1072 (22.9%) at 20. Alcohol use at 14 or younger was associated with eight times the odds of cocaine use at 17 (aOR 8.0, 95% CI 1.7–37.3) and 19 times at 20 (aOR 19.2, 95% CI 8.6–43.2). Peer cannabis use was associated with 7 times the odds of cocaine use at 17 (aOR 7.3, 95% CI 2.9–18.3) and double at 20 (aOR 2.4, 95% CI 1.8–3.2). Growing up in a neighbourhood where substance use was common doubled the odds of cocaine use at 17 (aOR 2.4, 95% CI 1.3–4.4). Shapley explanations revealed individual-specific positive or negative impacts of exposures.

Discussion
Cocaine use among 20-year-olds in Ireland is higher than reported internationally, and increases sharply between the ages of 17 and 20, suggesting a need for interventions targeting this age group. However, associations with early adolescent factors suggest that early interventions may also be important.

Background
The association between multidimensional household poverty (MHP) and child and mother psychopathology trajectories is not well understood. The aim of this paper is to explore this association.

Methods
We analysed 9241 infants and mothers recruited at 9-months (m) and 32-years (y) respectively from the Growing-up-in-Ireland study and followed up when the child was aged 3, 5, 7, 9 and 13y. MHP was derived from monetary, subjective and material poverty questionnaires completed by mothers before infant age 3y using latent-class-analysis. Confounder-adjusted linear spline multilevel models were used to examine the association between MHP before 3y and trajectories of child (3-to-13y) and mother (34-to-46y) psychopathology wellbeing measures (Strengths-and-difficulties-questionnaire and Centre-for-epidemiological-studies-depression-scale, respectively).

Results
In adjusted models, MHP before 3y was associated with a higher mean difference(MD) (MD:0.67, 95%CI 0.41,0.92) in child psychopathology at 3y and this was broadly similar at age 13y (MD:0.87, 95% CI 0.57,1.17). MHP prior to 3y was associated with a higher mother psychopathology when her child was age 3y (MD:1.07, 95% CI 0.90,1.23) and this persisted albeit with a slight reduction in magnitude at age 13y of the child (MD:0.72, 95% CI 0.53,0.90).

Conclusions
Though replication in other cohorts is required, findings suggest that MHP exposure in child infancy may have early negative life course impacts on mother and child wellbeing that persist for up to a decade. If causal, these findings underscore the importance of early life course policy interventions to prevent and ameliorate poverty to reduce long term psychopathology of mothers and their children.

This report draws on the Growing Up in Ireland (GUI) study to look at pornography use among over 4,500 young adults at 20 years of age. Pornography use was captured as part of a module of questions on different types of internet use. The rich information provided by the GUI study allows us to explore the potential influence of a range of factors on pornography use and to examine the way use is related to key aspects of wellbeing and sexual behaviour among young adults. Pornography use is found to be highly gendered, with 64 per cent of young men and 13 per cent of young women reporting use. For this reason, analyses in the report look separately at the factors for young women and men.

There has been a good deal of attention in Irish policy discourse to housing supply and affordability. However, there has been less focus on the extent to which the quality of housing impacts the wellbeing of children and their parents. This study addresses this gap in knowledge by using data from Growing Up in Ireland (GUI) Cohort ’08 to explore the influence of housing and neighbourhood quality on parental and child wellbeing. In particular, it looks at how the length of time households have spent experiencing inadequate housing can shape families’ wellbeing. The study adopts a multidimensional approach to measuring inadequate housing, capturing whether the home is unsuitable (in terms of size or problems like damp), whether the household struggles to adequately heat the home, lack of access to a garden or play space, the number of residential moves and the type of tenure. In addition, neighbourhood quality is assessed in terms of local disorder, having low social capital (with few family and friends in the area) and having access to fewer local services. Child wellbeing is measured using the Strengths and Difficulties Questionnaire (SDQ), which captures the extent of children’s socio-emotional difficulties.

This study draws on data on Growing Up in Ireland (GUI) Cohorts ’98 and ’08 to document changes in the lives of adolescents over the period 2011/12 to 2021/22, building on an earlier study (Smyth, 2022) which compared their experiences at nine years of age. This decade was a period of considerable social and policy change, including reform of the junior cycle, growing digitalisation and the disruption of the pandemic to all aspects of young people’s lives. Changes were also evident in the profile of young people and their families, with increasing cultural diversity, higher education levels among parents, lower levels of financial strain and increasing numbers with a disability among members of Cohort ’08 than among their older cohort counterparts. The study looks at changes in 13-year-olds’ relationships with their parents and peers, in their day-to-day activities and in their experiences of school. The main research questions addressed by the study are: How have the quality of relationships, experience of learning and activities engaged in by adolescents changed over the course of a decade? To what extent do any such changes reflect differences in the family characteristics of the young people? Are any such changes more evident for boys or girls or for young people from different social backgrounds? Is differentiation by gender and social background in adolescents’ social worlds less evident for the younger cohort than previously?

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.

This study investigates the long-term effects of victimization from middle adolescence to late adolescence and early adulthood, examining emotional and behavioral problems, peer relationships, and smoking habits and sleeping difficulties. The study also explores how these outcomes can persist into early adulthood, taking into consideration early victimization experiences, gender, cognitive ability, and family social class. The total sample included 7525 participants, spanning the ages of 13, 17, and 20, from the Child Cohort of the Growing Up in Ireland study (48.9% male). The path analysis model suggests that victimization is associated with behavioral problems at age 17, and it is also linked to emotional problems and sleeping difficulties at both ages 17 and 20. Additionally, sleeping difficulties, smoking habits, and indices of emotional and behavioral adjustment exhibit some stability between ages 13 and 17, as well as 17 and 20. Theoretical and practical implications are discussed.

Background
Poverty is associated with poor outcomes, yet exposure to distinct poverty trajectories in early childhood is not well understood.

Objective
To understand the prevalence of different trajectories of household poverty and their association with mid-childhood and mother indicators of physical health and psychopathology in Ireland.

Methods
We used a nationally representative, prospective cohort (Growing Up in Ireland–Infant Cohort). Household poverty included lowest third income decile, subjective poverty and material deprivation when children were aged 9 months, and 3, 5, 9 years. We used group-based multitrajectory cluster modelling to classify trajectories of poverty. Using multivariable logistic regression, adjusted with separate child and mother confounders, we assessed the association of poverty trajectories from 9 months to 9 years with child outcomes (overweight, any longstanding illness and psychopathology) at age 9 years and the same poverty trajectories over the same 9-year period with mother outcomes (overweight, any longstanding illness and depression).

Results
Of 11 134 participants, 4 trajectories were identified: never in poverty (43.1%), material/subjective>monetary poverty (16.1%), monetary>material poverty (25.6%) and persistent poverty (15.2%). Children in persistent poverty compared with those in never in poverty experienced higher odds of being overweight at 9 years (adjusted OR (aOR) 1.70, 95% CI 1.34, 2.16), having a longstanding illness (aOR 1.51, 95% CI 1.20, 1.91), and psychopathology (aOR 2.06, 95% CI 1.42, 2.99). The outcomes for primary parents (99.7% were mothers) were as follows: having higher odds of being overweight (aOR 1.49, 95% CI 1.16, 1.92), having a longstanding illness (aOR 2.13, 95% CI 1.63, 2.79), and depression (aOR 3.54, 95% CI 2.54, 4.94).

Conclusions
Any poverty trajectory was associated with poorer psychopathology and physical well-being in late childhood for children and their mothers in Ireland.