External Publications Using GUI Data

Importance Understanding which children in the general population are at greatest risk of poor functional outcomes could improve early screening and intervention strategies.

Objective To investigate the odds of poor outcomes in emerging adulthood (ages 17 to 20 years) for children with different mental health trajectories at ages 9 to 13 years.

Design, Setting, and Participants Growing Up in Ireland is a longitudinal, nationally representative population-based cohort study. Data collection began in August 2007 and was repeated most recently in September 2018. All results were weighted to account for sampling bias and attrition and were adjusted for socioeconomic factors. Data analysis took place from October 2022 to April 2023.

Exposure Four latent classes captured variation in mental health in children aged 9 and 13 years, based on the parent-completed Strengths and Difficulties Questionnaire. Classes included no psychopathology, internalizing, externalizing, and high (comorbid) psychopathology. Those who remained in the same class from ages 9 to 13 years were included.

Main Outcomes and Measures Poor functional outcomes in emerging adulthood were measured at approximate ages 17 years (range, 16 to 18 years) and 20 years (range, 19 to 21 years). Outcomes included poor mental health, poor physical health, social isolation, heavy substance use, frequent health service use, poor subjective well-being, and adverse educational/economic outcomes.

Results Of 5141 included participants, 2618 (50.9%) were male. A total of 3726 (72.5%) were classed as having no childhood psychopathology, 1025 (19.9%) as having persistent externalizing psychopathology, 243 (4.7%) as having persistent internalizing psychopathology, and 147 (2.9%) as having persistent high psychopathology. Having any childhood psychopathology was associated with poorer functional outcomes in emerging adulthood. The internalizing group had elevated odds of most outcomes except for heavy substance use (range of odds ratios [ORs]: 1.38 [95% CI, 1.05-1.81] for frequent health service use to 3.08 [95% CI, 2.33-4.08] for poor mental health). The externalizing group had significantly elevated odds of all outcomes, albeit with relatively small effect sizes (range of ORs: 1.38 [95% CI, 1.19-1.60] for frequent health service use to 1.98 [95% CI, 1.67-2.35] for adverse educational/economic outcomes). The high psychopathology group had elevated odds of all outcomes (nonsignificantly for frequent health service use), though with wide confidence intervals (range of ORs: 1.53 [95% CI, 1.06-2.21] for poor physical health to 2.91 [95% CI, 2.05-4.12] for poor mental health). Female participants with any psychopathology had significantly higher odds of poor physical health and frequent health service use compared with male participants with any psychopathology.

Conclusions and Relevance In this longitudinal cohort study, childhood psychopathology was associated with a widespread pattern of functional impairment in emerging adulthood. Findings point to the need for a wider range of preventive interventions in child and adolescent mental health services.

Importance Birth weight percentiles (BWPs) are often dichotomized at the 10th percentile and show statistically significant association with later cognitive performance, for both preterm and term-born children. However, research testing nonlinear associations between BWPs and cognitive performance is scarce.

Objective To investigate culturally invariant, nonlinear associations of BWPs and gestational age with later cognitive performance.

Design, Setting, and Participants In this cohort study, participants with valid neonatal and cognitive data were combined from 4 observational cohorts, including the Millennium Cohort Study, the National Longitudinal Survey of Youth 1979 Child and Young Adult cohort, Growing Up in Ireland, and the Longitudinal Study of Australian Children, with children born between 2000 and 2002, 1980 and 2010, 2007 and 2008, and 2003 and 2004, respectively. Neonatal data were parent reported before age 1 year. At approximately 5 years of age, multiple cognitive tests were performed. Follow-up at 5 years of age was the predominant focus. Data were analyzed July 17, 2023.

Exposure The parent-reported neonatal data were used to calculate BWPs according to the Fenton growth chart.

Main Outcome and Measure Scores for IQ were created from multiple measures of cognition, which were z standardized separately within each cohort.

Results Of 30 643 participants (50.8% male), 7.5% were born preterm (before 37 weeks gestation) and 92.5% were term born (between 37 and 42 weeks gestation). In the pooled data using multivariate adaptive regression splines, IQ linearly increased by 4.2 points as BWPs increased from the first to the 69th percentile before completely plateauing. For gestational age, IQ linearly increased by 1.3 points per week up until 32 weeks, with the association reducing to 0.3 points per week after 32 weeks. The association of BWP with IQ was not moderated by gestational age. For term-born infants, the estimated IQ score was only clinically meaningfully lower than average when birth weight was below the third percentile. Consistent results were found when instead using multivariable regression where gestational age and BWPs were categorized into groups.

Conclusions and Relevance In this cohort study, lower BWPs and gestational age were independently associated with lower IQ. For term-born infants, a cutoff of the third percentile would be more appropriate than the traditionally used 10th percentile when the aim is estimating meaningful cognitive differences.

Multiple factors including the child’s non-linguistic characteristics and caregiving environment can affect language development. Since preterm birth (<37 weeks’ gestation) can negatively affect language development, this study used path analysis to investigate whether the influence of preterm birth on expressive language development at 3 and 5 years of age is mediated by a child’s non-linguistic characteristics (temperament and cognitive, motor, and social-personal abilities), caregiving environment (maternal and paternal stress and depression, mother-child and father-child relationship quality), and interactions between these domains. These analyses were conducted using three waves of data (ages: 9 months, 3 years, 5 years) on 8,712 children (4,300 female; 535 preterm) from a nationally-representative longitudinal study in Ireland. Preterm birth was indirectly (but not directly) associated with expressive language at 3 years of age via cognitive and social-personal abilities (but not motor abilities, mother-child relationship quality, or father-child relationship quality) at 9 months. There was no direct or indirect effect of preterm birth on expressive language at 5 years of age. Preterm birth negatively affected mother-child and father-child relationship quality at 3 years via fussy-difficult temperament and mother’s/father’s stress (but not depression) at 9 months. These findings are discussed with reference to international standards for neonatal care, including the need for long-term developmental monitoring of children born preterm by multidisciplinary healthcare teams, alongside parental supports promoting mental health and confidence in caregiving tasks. Future study recommendations are made to expand the tested models in line with family systems perspectives.

The internet provides opportunities for social interactions which first occur in an online environment that can lead to meeting up in real life. However, growing concerns around safety and privacy warrant greater study of this modern-day phenomenon. Using a longitudinal dataset of approximately 4,300 20-year-olds in Ireland, this study finds one-in-three report meeting someone from online. Multiple regression reveals that females are less likely to engage in such behaviour, while the trait of ‘openness’, spending more time on the internet, being non-heterosexual, using dating apps, and being sexually active at 17 years are positively associated. Early exposure to information and communication technologies, as indicated by mobile phone ownership at 9 years, is also associated with online-to-offline encounters. A range of policy considerations are discussed, including the continued need for education in e-safety and cyber safety awareness from a young age through young adulthood, particularly for groups such as LGBT communities.

Although there is a wealth of research addressing the association between mental health and school absenteeism, there are calls for a better understanding of how mental health difficulties might predict SAPs (Egger et al., 2003; Finning et al., 2022; Ingul et al., 2019; Wood et al., 2012). The aim of this paper was to create a more nuanced understanding of SAPs by exploring how different constellations of mental health difficulties might be predictive of absenteeism in 9-year-olds. Using a sample of Irish 9-year-olds (N = 8570) from the Growing Up In Ireland Study (GUI’98), the research used latent class analysis (LCA) to identify combinations of mental health symptoms. Twenty items from the Strengths and Difficulty Questionnaire (SDQ) were used to measure a range of emotional and behavioural difficulties. The analysis yielded four mental health classes—High Risk of Emotional and Behavioural Difficulties (EBD), High Risk of Emotional Difficulties (ED), High Risk of Behavioural Difficulties (BD) and Low Risk of Emotional and Behavioural Difficulties (EBD). The study assessed whether rates of student absenteeism varied across different classes of mental health as identified through LCA and explored risk factors associated with different classes. Children in the high-risk mental health symptomology groups had significantly higher odds of absenteeism compared to the low-risk class and significantly greater odds of experiencing multiple family, school and demographic risk factors. The distinct profiles of mental health symptoms observed within the classes and their patterns of associations with risk factors and days absent indicated classes were theoretically distinct. The results illustrate the importance of recognising the relationship between mental health and school absenteeism in primary school children when developing early intervention strategies for SAPs. As one of the few studies to focus on 9-year-olds, the current study contributes to current knowledge on the complexities of emerging SAPs in primary school children.

Keywords
Mental health, School attendance problems, School avoidance, Truancy, Risk factors

This study investigates the relationship between multidimensional household poverty and cognitive and behavioural development during the formative years of childhood (from 9 months to 9 years), using nationally representative longitudinal data from Ireland for the cohort of children born in 2007-2008. The results indicate substantial inequalities in Irish children’s cognitive and behavioural outcomes at age 9 by multidimensional poverty duration. Children with at least one spell in poverty (out of four interviews) have worse cognitive and behavioural outcomes. Dynamic structural equation models provide evidence in support of a hybrid family investment/family stress model. Although family investment processes account for some of the cumulative effects of childhood poverty on cognitive outcomes, family stress processes help explain the links between poverty and both cognitive and behaviour outcomes in early childhood. Overall, poverty is strongly related to child outcomes over time via the direct effects of current poverty on child outcomes and path dependency in both poverty and child outcomes over time. There are also indirect effects via the two child outcomes reinforcing each other as children grow older (with the effects of behaviour problems dominating those of cognitive ability), even as the parental investment and maternal stress pathways become less pronounced.

Keywords
Early childhood, child poverty, cognitive ability, behaviour problems, growing up in Ireland

International research has shown that civic engagement, that is, volunteering in local services, can benefit both young people and their communities, while political engagement can strengthen a society’s democratic culture. The Better Outcomes, Brighter Futures (2019) policy framework highlights the importance of young people feeling connected, respected and contributing to their world. To date, however, there has been an absence of systematic research on this aspect of young people’s transition to adulthood in Ireland. Further, although the government strategy Our Rural Future highlights a lack of access to facilities and transport for young people living in rural areas, little is known about how this might impact on their civic and political engagement. It is therefore crucial to have an evidence base to identify the drivers of civic engagement in order to better support young people’s involvement. This study aims to fill this gap by drawing on rich information on 20 year olds from Cohort ’98 of the Growing Up in Ireland (GUI) study.

Background
Children with a parent who smokes are more likely to become substance users than those who do not have a parent who smokes. In this study, we examined whether childhood or early adolescent exposure to primary parent smoking increased the risk of subsequent teenage alcohol and drug use at ages 17–18 years.

Methods
For this longitudinal observational study, we analysed data from 6039 teenagers and their parents from the waves 1–3 of the Growing up in Ireland Cohort 98’ Study. Parental smoking was assessed at baseline (9 years) and wave 2 (13 years) with responses coded as yes or no. The primary parent was defined as the person who provided most care and who knew most about the Study Child, usually the mother or mother figure for 98% of study participants. Teenage alcohol and drug use assessed at ages 17–18 years (wave 3) was determined by responses to the question “Have you ever consumed alcohol?” (answers yes or no), drug use was assessed by questions on ever trying aerosols/gas, cannabis, and non-prescribed drugs, with those answering yes being classified as other-drug ever users. We did a logistic regression analysis to examine the associations between parents’ smoking on teenage alcohol and drug use, controlling for covariates: gender, education, income, education, region, and household type. Ethics approval for the GUI project was obtained from the Health Research Board.

Findings
Of the 6039 teenagers included in our study, 2968 (49%) were female, 3070 (51%) were male, 5351 (89%) ever used alcohol, 5065 (85%) were current users, and 2098 (35%) used other drugs. Rates of primary parent smoking were 31% (n=1883) in wave 1 and 30% (n=1829) in wave 2. After adjusting for other exposures known to be associated with teenage substance use, primary parent smoking at waves 1 and 2 was associated with higher odds of teenage alcohol ever use (adjusted odds ratios [aORs] 1·89 [95% CI 1·44–-2·46] at wave 1 and 1·53 [1·20–1·98] at wave 2), current alcohol use (1·88 [1·50–2·36] and 1·59 [1·28–1·97]) and other-drug ever use (1·699 [1·45–1·95] and 1·71 [1·47–1·98]).

Interpretation
Teenagers aged 17–18 years exposed at ages 9 and 13 years to parental smoking were more likely to report significantly higher odds of alcohol and drug use at age 17–18 years. The finding that exposure to parent smoking in childhood increases the risk of teenage alcohol and other drug use suggests a need for interventions aimed at parents who smoke Limitations include potential unmeasured or residual confounders and reliance on self-reported teenage substance use behaviours.

Funding
Royal City of Dublin Hospital Trust, Irish Research Council Government of Ireland Postgraduate Scholarship Programme.

While research has investigated the effects of the Great Recession on the Irish economy using economic indicators or cross-sectional household-level data, this research note applies group-based multitrajectory modelling to provide a more nuanced approach. Using nationally representative, longitudinal data from the Growing Up in Ireland study, we analyse patterns in three common measures of economic well-being (financial strain; disposable income; material deprivation) across Irish households in the period leading up to, during and after the Great Recession, and subsequently, break down the characteristics for each group of trajectories. We identify six distinct trajectory clusters, which all indicate declining income and increasing financial strain from the start to the height of the economic depression. However, trajectory groupings show that experiences were far from uniform, with previous economic well-being and demographic characteristics shaping the household experience. Implications for future research are discussed.

A small minority of Irish students attend fee-charging second-level schools. However, media analyses of the backgrounds of those students who go on to more sought-after tertiary educational institutions or degree courses suggest that a disproportionate number of them were attendees at fee-charging schools. There are a few reasons why this might be the case. In this analysis, the longitudinal data points of the Growing Up in Ireland (GUI) study are exploited to weigh up the evidence behind differing explanations. An estimated measure of Leaving Certificate success was generated for 3105 participants in wave 4 of the GUI. From waves 1 and 2, the ability of those participants was calculated based on their performance in several standardised tests taken prior to attending second-level school. The analysis found that while the students who attended fee-charging schools were about 9% ahead in Leaving Certificate performance, they had roughly the same lead in measured ability on entry into the second-level schools. The analysis found a significant but marginal positive effect on attending private schools. This result is in line with the general international findings. Ireland’s hybrid funding structure for fee-paying schools is discussed. Gender and household income effects were noted.

Keywords
Longitudinal data, non-state schools, ability, exam performance, school value added

Introduction
Despite a growing body of research on associations between adolescent digital use and well-being, few studies have investigated these associations a) longitudinally and b) across socioeconomic status. The present study uses high-quality longitudinal data to examine how digital engagement shapes socioemotional and educational outcomes from early to late adolescence across socioeconomic status (SES).

Methods
Participants are 7685 individuals (49.0% female) from the 1998 birth cohort of the longitudinal Growing Up In Ireland (GUI) survey. The survey was administered to Irish parents and children between 2007 and 2016 (at ages 9, 13, and 17/18). Fixed-effects regression modeling was used to establish associations between digital engagement and socioemotional and educational outcomes. Further Fixed-Effects models were analyzed separately by SES, to assess how associations between digital use and adolescent outcomes differ by socioeconomic groups.

Results
Results show that digital screen time increases markedly from early to late adolescence, but to a higher extent among low-SES versus high-SES groups. Heavy levels of digital screen time (i.e., 3+ hours daily) are associated with declines in well-being, particularly for external and prosocial functioning, while engagement in learning-oriented digital activities and gaming is associated with better adolescent outcomes. Yet, low-SES adolescents are globally more harmed than high-SES adolescents by their digital engagement, and high-SES adolescents benefit more from moderate levels of digital use and from engaging in learning-oriented digital activities.

Conclusions
This study suggests that digital engagement is associated with socioeconomic inequalities in adolescents’ socioemotional well-being and, to a lesser extent, educational outcomes.

Background
Ireland has one of the lowest BF rates in the world. This study investigates the association between breastfeeding and infant health in Ireland.

Methods
A cross-sectional, secondary analysis of data collected from Growing Up in Ireland (GUI): the National Longitudinal Study of Children was conducted. The average morbidity for 2212.

infants exclusively breastfed for at least 90 days (EBF90days) was compared to data for 3987 infants in the non-breastfed (Non-BF) group. Data were weighted using entropy balancing to ensure the comparability of groups. Sensitivity analyses considered alternative definitions of the breastfeeding group.

Results
Infants who were EBF90days were significantly less likely to be admitted to hospital (CI: − 0.06 to − 0.03), spent less nights in hospital (CI: − 0.37 to − 0.11), and were less likely to develop respiratory diseases including asthma (CI: − 0.03 to − 0.01), chest infections (CI: − 0.12 to − 0.08), snuffles/common colds (CI: − 0.07 to − 0.02), ear infections (CI: − 0.08 to − 0.04), eczema (CI: − 0.08 to − 0.04), skin problems (CI: − 0.04 to − 0.00), wheezing or asthma (CI: − 0.06 to − 0.03), vomiting (CI: − 0.03 to − 0.00), and colic (CI: − 0.04 to − 0.01). Further outcomes such as current health of the infant at time of interview (CI: − 0.04 to − 0.00), feeding problems (CI: − 0.04 to − 0.02) and sleeping problems (CI: − 0.02 to − 0.00) indicated a protective effect of EBF90days versus Non-BF. However, these infants were also more likely to fail to gain weight (CI: 0.01 to 0.02) and were at a slightly higher risk of developing nappy rash (CI: 0.00 to 0.02).

Conclusion
Exclusive breastfeeding for 90+ days is associated with protection against childhood morbidity. Given the protective effect of breastfeeding on adverse health effects in infants, policy makers should prioritise policies that support, promote and protect exclusive breastfeeding.

Self-harm in adolescents and young adults (AYAs) is the result of a complex interaction of biological, psychiatric, psychological, social, and cultural risk factors. A lot of research has already been conducted to identify the risk factors for self-harm in AYAs. On the other hand, there has been less research conducted on the simultaneous effects of, and the interactions between, multiple risk factors for self-harm in heterogeneous AYA individuals. In this study, we conducted a latent class analysis (LCA) of three waves from the Growing Up in Ireland (GUI) longitudinal cohort study at ages 13, 17 and 20 to identify homogenous subgroups of AYA individuals who exhibit similar risk markers for self-harm at these three time points. Then, we evaluated the risk that these subgroups ever self-harmed by age 17, self-harmed at age 20, or were persistently self-harming across both time points. The most at-risk group appeared to be the individuals aged 17 who had been diagnosed with depression/anxiety. Compared to the low-risk-marker group, the ‘diagnosed with depression/anxiety’ group had a 30-fold risk of self-harm at age 17, and 32-fold risk of persistently self-harming by age 20. The ‘undiagnosed but high depression’ group at this time point was also at significant risk of self-harm. This research enables us to understand which risk markers tend to co-occur together and will help to identify high-risk groups for self-harm both clinically and in the community. An investigation of risk markers like this can potentially be used in the design of public health interventions to reduce the burden of self-harm, and indeed suicide, in young people.

Key messages

• We identified sub-groups of young people with a high-risk of self-harm and suicide from the general population.

• These identifiable sub-groups can inform intervention policies and strategies for prevention programmes both in clinical and non-clinical settings like schools.

For the first time, data on children and adolescents with disabilities in Ireland are reported based on the Active Healthy Kids Global Alliance Para Report Card methodology. The most recent data from the last 10 years were used in the grading process (A+ to F), and indicators with insufficient data were graded as incomplete. Of the 10 indicators from the Global Matrix Para Report Cards, grades were assigned to Overall Physical Activity (F), Organized Sport (D), Active Transport (D−), Sedentary Behaviors (D−), Family & Peers (C), School (C−), Community & Environment (B−), and Government (B). Irish disability sport organizations were invited to assess the research-led audit and provided commentary around the final grading. The contextual discussion of the grades is presented through the lens of strengths, weaknesses, opportunities, and threats with the purpose being to provide direction for the reduction of physical activity disparities among children with disabilities.

The microbiome-gut-brain axis plays a role in anxiety, the stress response and social development, and is of growing interest in neuropsychiatric conditions. The gut microbiota shows compositional alterations in a variety of psychiatric disorders including depression, generalised anxiety disorder (GAD), autism spectrum disorder (ASD) and schizophrenia but studies investigating the gut microbiome in social anxiety disorder (SAD) are very limited. Using whole-genome shotgun analysis of 49 faecal samples (31 cases and 18 sex- and age-matched controls), we analysed compositional and functional differences in the gut microbiome of patients with SAD in comparison to healthy controls. Overall microbiota composition, as measured by beta-diversity, was found to be different between the SAD and control groups and several taxonomic differences were seen at a genus- and species-level. The relative abundance of the genera Anaeromassillibacillus and Gordonibacter were elevated in SAD, while Parasuterella was enriched in healthy controls. At a species-level, Anaeromassilibacillus sp An250 was found to be more abundant in SAD patients while Parasutterella excrementihominis was higher in controls. No differences were seen in alpha diversity. In relation to functional differences, the gut metabolic module ‘aspartate degradation I’ was elevated in SAD patients. In conclusion, the gut microbiome of patients with SAD differs in composition and function to that of healthy controls. Larger, longitudinal studies are warranted to validate these preliminary results and explore the clinical implications of these microbiome changes.

While problems in the housing system in Ireland have been under the spotlight for the last decade, relatively little attention has been paid to the experience of children and to the consequences of housing issues for child development. International research has highlighted a range of effects of poor housing on children. Poor physical housing conditions has been associated with respiratory illnesses and childhood accidents. Overcrowding has been linked to poorer educational outcomes and deprived neighbourhood conditions to socio-emotional problems. Frequent residential mobility has also been found to lead to poorer cognitive and non-cognitive outcomes. However, there is a lack of evidence on how far these findings apply in Ireland where levels of home ownership are high and levels of neighbourhood segregation are lower. This study addresses this gap. Drawing on data from the ’08 Cohort of the Growing Up in Ireland study, we explore the housing conditions faced by children in early and middle childhood and the implications of these housing experiences for their cognitive, socio-emotional and health outcomes. We adopt a multi-dimensional approach to measuring housing conditions, incorporating housing tenure, suitability of accommodation, heating deprivation, neighbourhood disorder and housing mobility.

Despite the right of disabled people to full social and economic inclusion, many face multiple day-to-day and systemic challenges. These include but are not limited to additional expenses, access to housing, and everyday accessibility difficulties. Surveys show the general public hold positive attitudes towards policies that seek to enable disabled people to overcome these challenges, but standard survey methods are susceptible to response biases that may overestimate this support. This study aimed to test whether two such biases influence support for disability policy in Ireland: social desirability bias (i.e. the tendency for survey respondents to alter their responses in order to present themselves in a positive light); and inattention to the implications of policy support (e.g. that welfare policies require funding). Together the survey experiments covered a range of policy issues and types of disability, as identified in previous research and in consultation with the disability advisory group for the project.

Background
Physical activity (PA) can reduce young peoples’ risk of depressive symptoms. Associations between PA and depressive symptoms are often investigated over timeframes spanning minutes to weeks. Less is known about whether childhood/adolescent PA can predict depressive symptoms in early adulthood.

Methods
Using a nationally representative sample from Ireland, latent growth mixture modelling was performed to investigate the extent to which different PA trajectories existed from ages 9–17, whether gender, weight status, and socio-economic deprivation at age 9, predicted PA trajectories from ages 9–17, and whether trajectory class membership predicted depressive symptoms at age 20.

Results
A 4-class solution was the best fit to the data (AIC = 52 175.69; BIC = 52 302.69; ssaBIC = 52 245.49; entropy = 1.00). Classes were labelled according to their baseline PA and slope of their trajectory: ‘High-Decreasers’; ‘Moderate-Decreasers’; ‘Moderate-Stable’; and ‘Low-Increasers’. A negative linear association existed between activity trajectory and the likelihood class members were female, overweight or socioeconomically deprived at age 9. The most active class (High-Decreasers) were significantly less likely to report depressive symptoms at age 20 than other classes.

Conclusions
Multiple PA trajectories exist throughout childhood and adolescence although differences in PA levels reduced over time. The most/least active children continued to be the most/least active throughout adolescence. Those most active were least at risk of depressive symptoms in early adulthood. Being female, overweight or experiencing deprivation at age 9 were all risk factors for inactivity throughout adolescence. Findings have implications for public health and PA promotion in young people

This chapters addresses digital inequalities in young people’s daily lives and well-being. The chapter examines how adolescents’ digital engagement differs across family socioeconomic status (SES) and gender, and how it relates to their mental health outcomes. Analyses use longitudinal data from the Growing Up in Ireland study from age 9 to 18, combined with cross-national data from the Health Behaviour in School-Aged survey on adolescents aged 11-15 across 35 industrialised countries. Longitudinal analyses reveal that low-SES adolescents and girls experience higher mental health problems as they increase their time using digital devices, compared to high-SES adolescents and boys. Cross-national analyses indicate that, while boys spend more time in digital activities, girls are at higher risks of experiencing mental health problems from engaging with digital activities. However, the magnitude of these gendered patterns differs markedly across national contexts. Cross-country comparisons on SES yield mixed results: in some countries low-SES adolescents are mentally more harmed by their digital engagement (i.e., Switzerland, Austria, Norway), but in other countries high-SES adolescents are those at higher mental health risks from using digital devices (i.e., Portugal, Czech Republic, Bulgaria). The chapter findings are discussed within the existing literature on digital inequalities and young people’s well-being.