External Publications Using GUI Data

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.

Objective
This study examines the association between attention-deficit/hyperactivity disorder (ADHD) and overweight/obesity in a large-scale longitudinal study of children, while controlling for a range of psychosocial factors.

Method
Data were obtained from Growing Up in Ireland, a nationally representative and longitudinal study of approximately 6500 children who were assessed at 9 and 13 years of age. Body mass index (BMI) was determined using measured height and weight, ADHD status was determined by parent reports of professional diagnoses and ADHD symptoms were measured using the Strengths and Difficulties Questionnaire (SDQ).

Results
The associations between ADHD status, ADHD symptoms (SDQ) and BMI category at age 9 and 13 years were evaluated using logistic regression. Adjustments were made for child factors (sex, developmental coordination disorder, emotional symptoms, conduct problems, birth weight and exercise) and parental factors (socio-economic status, parental BMI, parental depression, and maternal smoking and alcohol use during pregnancy). Logistic regression indicated that ADHD status was not associated with BMI category at 9 or at 13 years of age, but children with ADHD at 9 years were significantly more likely to be overweight/obese at 13 years than those without ADHD. However, when other child and parental factors were adjusted for, ADHD status was no longer significantly associated with weight status. Female sex, low levels of exercise, overweight/obese parents and prenatal smoking during pregnancy consistently increased the odds of childhood overweight/obesity.

Conclusions
While ADHD and overweight/obesity co-occur in general populations, this relationship is largely explained by a variety of psychosocial factors.

Keywords
ADHD, longitudinal, obesity, overweight, psychosocial

Objective
To examine the extent to which early child nutrition, maternal antenatal lifestyle behaviours and child diet and lifestyle explain social class inequalities in the risk of rapid weight gain between birth and 3 years and obesity at age 3 years.

Design
A longitudinal and prospective birth cohort study.

Subjects
Nationally representative sample of 11 134 children and their parents followed from 9 months of age until 3 years. Child weight and maternal height and weight were measured at 9 months and 3 years and child birth weight was extracted from hospital records. Other predictors of child growth and obesity were collected by maternal report at 9 months and 3 years.

Results
Although born lighter on average, children of unskilled manual parents were 274 g heavier than children of professional parents by 3 years of age. The fully adjusted model of rapid growth from birth to 3 years of age and obesity at 3 years of age accounted for all social class differentials. Breastfeeding and age at the introduction of solids were associated with the largest average reduction (41%) in the odds ratio (OR) of rapid growth in the first 9 months of life for each class relative to the professional class. In the period from 9 months to 3 years of age, the class differential in rapid growth was reduced most by measures of the child’s diet and lifestyle. However, the impact of the groups of predictors varied by social class. For early life growth, among the non-manual classes the proportionate reductions are largest when adjusted for early infant nutrition, whereas maternal prenatal smoking is more important for the manual social classes.

Conclusion
Preventative interventions to reduce levels of childhood obesity should be multi-dimensional but different dimensions should be given more or less significance depending on socio-economic group.

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.

Objective
To longitudinally investigate body mass index (BMI) in young children in Ireland and identify factors and critical time points associated with changes in BMI.

Study design
Data on 11 134 children were collected in the nationally representative Growing Up in Ireland infant cohort study. Height and weight were measured at 9 months, 3 years, and 5 years of age. Multilevel regression was used to identify risk factors associated with changes in BMI over time (n = 10 377), combining a unique set of covariates collected from the child and the 2 main caregivers (usually the mother and father).

Results
The proportion of children ≥85th percentile of World Health Organization growth criteria was 39% at 9 months, 44% at 3 years, and 30% at 5 years. Children born large for gestational age (13%) and those with rapid infant weight gain (25%) consistently had higher BMI. Low average BMIs were consistently seen in children born small for gestational age (10%) or before 37 weeks (7%). Smaller variations in BMI existed for other factors including ethnicity, household structure, caregiver weight status, breastfeeding, sex, socioeconomic status, sleeping hours, childcare, and region.

Conclusions
In this study, differences at birth and in infancy appear to be most strongly associated with variation in BMI at all ages. Nevertheless, belonging to a number of other high-risk groups cumulatively could lead children to develop critical weight states. Policy-makers should target families with interventions before and during pregnancy when dominant risk factors are still modifiable. Longer-term follow-up of children may be needed to study associations later in childhood.

Keywords
Growing Up in Ireland, body mass index, childhood obesity, growth trajectories, multilevel modelling

Objectives
Maternal health behaviours (MHBs) can influence pregnancy outcomes. Despite efforts internationally to encourage positive MHBs, women often fail to comply with pregnancy guidelines. International studies show differences in MHBs between nationalities and an effect of time spent in the host country. There is limited Irish data in this area, with no previous research relating to the effect of time in Ireland.

Study design
This study is a cross-sectional analysis of the Growing Up in Ireland infant cohort, a nationally representative longitudinal study.

Methods
Examination of the MHBs of non-Irish nationals during pregnancy and the effect of time in Ireland on the said behaviours.

Results
An association was found between time spent in Ireland and increased alcohol consumption prevalence. Those living in Ireland for ≤5 years were 60.8% less likely to consume alcohol during pregnancy (0.000) and 29.3% less likely to take folic acid before conception (0.021). Those who smoked during pregnancy were 98.6% more likely to consume alcohol (0.000) and those who consumed alcohol were 95.2% more likely to smoke during pregnancy (0.000).

Conclusions
The results demonstrate differences in MHBs and the influence of time living in Ireland. These findings are of relevance for policy and intervention planning to optimise pregnancy outcomes among non-nationals.

Objectives
Migrant youths endure many challenges. Such challenges can be stressful and lead to psychological difficulties. We investigated the relationship between migration, psychopathology and stressful events in children and adolescents. We hypothesised that migrant youths would show higher levels of psychopathology and more stressful life events than non-migrant youths.

Method
Using the Child cohort (Cohort ‘98) of the ‘Growing up in Ireland’ study we investigated psychopathology, as measured by the Strengths and Difficulties questionnaire (SDQ) at age 9 and 13 and stressful life events in migrant and non-migrant youths.

Results
There was no significant difference between the proportion of migrant and non-migrant youths reporting psychopathology in childhood (p>0.05) or adolescence (p>0.05). Analysis of the SDQ subscales revealed that a significantly greater proportion of migrant youths had hyperactivity problems in childhood (p = 0.04) but a greater proportion of non-migrant youths had emotional problems in early adolescence (p = 0.04). We found that migrant youths experienced significantly more stressful life events than their non-migrant counterparts (p<0.01), however, once ‘Moving house/country‘ was removed as a stressor, there was no difference between the groups (p>0.27).

Conclusions
Contrary to our hypothesis, we observed that there were few differences between migrant and non-migrant youths in the levels of psychopathology. Migrant youths experienced a greater number of stressful life events, however, this was attributable to stressors relating to moving. An increased understanding of the factors promoting resilience, as demonstrated by the migrant youths, could aid health professionals and policy makers to effectively tailor interventions for mental health promotion.

Keywords
Early life stress, immigration, migrants, psychopathology

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

Objectives
To examine the associations between preeclampsia and longitudinal child developmental and behavioural outcomes using data from a nationally representative study of children living in Ireland.

Methods
We used maternal-reported data from the Growing Up in Ireland longitudinal study of children. Data on preeclampsia and preeclampsia + small for gestational age (SGA) were collected when children were 9-months old. Data on child development and behavioural outcomes were collected at 9-months using the Ages and Stages Questionnaire (ASQ), and at 3 years, 5 years and 7–8 years using the Strengths and Difficulties Questionnaire (SDQ). Multivariate logistic regression analysis was used to examine the association between preeclampsia exposure and failure of ASQ domains, and abnormal SDQ domains. Linear spline multilevel models were used to examine the association between preeclampsia and preeclampsia + SGA and repeated measures of SDQ. All models controlled for several perinatal and sociodemographic factors.

Results
A total of 10,692 children were included in the study at baseline, representing a weighted total of 70,791. Multivariate logistic regression suggested that preeclampsia was not associated with failing any ASQ domain. Preeclampsia was associated with abnormal SDQ cut-off of emotional (≥ 5) and hyperactivity (≥ 7) domains at age 5 years only. In the linear spline model, mean SDQ score was higher at each time point in exposed groups.

Conclusions for Practice
While we did not find strong evidence of associations between preeclampsia and child developmental and behavioural outcomes overall, some associations between preeclampsia-exposure and subtle behavioural issues did persist. Further research is needed to replicate these findings, and determine the clinical significance of changes in SDQ scores.

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.

Purpose
The aim of this study is to examine the association between household energy poverty (EP) and trajectories of emotional and behavioural difficulties during childhood.

Methods
The Growing up in Ireland study is two nationally representative prospective cohorts of children. The Infant Cohort (n = 11,134) were recruited at age 9 months (9 m) and followed up at 3, 5, 7 and 9 years (y). The Child Cohort (n = 8,538) were recruited at age 9 y and followed up at 13 y and 17/18 y. EP was a composite of two relative measures of EP. Emotional and behavioural difficulties were repeatedly measured using the strengths and difficulties questionnaire (SDQ). Linear spline multilevel models were used, adjusted for confounders to examine the association between (1) EP (9 m or 3 y) and trajectories of emotional and behavioural difficulties from 3 to 9 y in the Infant Cohort and (2) EP at 9 y and the same trajectories from 9 to 18 y in the Child Cohort.

Results
In adjusted analyses, EP at 9 m or 3 y of age was associated with higher total difficulties score at 3 y (0.66, 95% CI 0.41, 0.91) and 5 y (0.77, 95% CI 0.48, 1.05) but not at 7 y or 9 y. EP at 9 y was associated with higher total difficulties score at 9 y (1.73, 95% CI 1.28, 2.18), with this difference reducing over time leading to 0.68 (95% CI 0.19, 1.17) at 17/18 y.

Conclusions
Our study demonstrates a potential association between early life EP and emotional and behavioural difficulties that may be transient and attenuate over time during childhood. Further studies are required to replicate these findings and to better understand if these associations are causal.

Purpose
The purpose of this paper is to explore the factors associated with occupational stress and job satisfaction among Irish primary school principals. A principal’s job has become increasingly demanding and complex in recent decades. However, there is little current research into their levels of stress and job satisfaction, particularly based on nationally representative data. In order to understand how principals perceive their job and how best to support them, new insights into factors contributing to job satisfaction and stress of school principals are warranted.

Design/methodology/approach
The paper draws on an analysis of Growing up in Ireland data, a national representative study of nine-year-old children in Ireland. In order to explore the simultaneous impact of individual and school factors on stress and job satisfaction of principals in Irish primary schools, multivariate analysis was used. Analyses in this paper are based on responses from principals in 898 schools.

Findings
The results of the study indicate that a significant number of primary school principals in Ireland are not very satisfied and feel stressed about their job. Regression analysis revealed that job satisfaction and occupational stress were related to a complex set of personal characteristics, working conditions, school context and teacher climate.

Research limitations/implications
The data are limited to primary school principals. However, this is in itself an advantage since it allows for greater insights into variation across principals in job satisfaction and stress, holding the effect of school level constant.

Originality/value
This is the first study of its kind in the Irish context that explores the simultaneous effect of a number of factors on school principals’ stress and job satisfaction.

Keywords
Job Satisfaction, Ireland, Occupational stress, Primary schools

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.

Purpose
We investigated the hypothesis that mode of delivery affects childhood behavior and motor development and examined whether there are sex-specific associations, i.e., whether males and females have different risk estimates.

Methods
Families with infants born between December 2007 and May 2008 (N = 11,134) were randomly selected and recruited to the Growing Up in Ireland study. Mode of delivery was classified into spontaneous vaginal delivery; instrumental vaginal delivery; emergency Cesarean section (CS); and elective CS. The ‘Ages and Stages Questionnaire’ was completed at age 9-months and the ‘Strengths and Difficulties Questionnaire’ at 3 years. Data were weighted to represent the national sample (N = 73,662) and multivariate logistic regression was used for the statistical analyses.

Results
At age 9 months, elective CS was associated with a delay in personal social skills [adjusted odds ratio, aOR 1.24; (95 % confidence interval, CI 1.04, 1.48)] and gross motor function [aOR 1.62, (95 % CI 1.34, 1.96)], whereas emergency CS was associated with delayed gross motor function [aOR 1.30, (95 % CI 1.06, 1.59)]. At age 3 years there was no significantly increased risk of an abnormal total SDQ score across all modes of delivery.

Conclusions
Children born by elective CS may face a delay in cognitive and motor development at age 9 months. No increase in total SDQ score was found across all modes of delivery. Further investigation is needed to replicate these findings in other populations and explore the potential biological mechanisms.

Purposes
Dietary free sugars (FS) are the most important risk factor for dental caries and can contribute to excess energy intake. Measuring FS intake is limited by food composition databases and appropriate dietary assessment methods. The aim of this analysis was to estimate total sugar (TS) and FS intakes for Irish pre-schoolers and examine the proportion of dietary TS and FS captured using a short food questionnaire (SFQ).

Methods
This is a secondary analysis of 3-year-old children from two national surveys; Growing Up in Ireland (GUI), N = 9793 of whom 49% were girls and the National Preschool Nutrition Survey (NPNS), N = 126 and 52% were girls. GUI used SFQs and NPNS used semi-weighed food diaries to collect dietary data from 3-year-old children. Dietary intake databases were linked using an established approach. Mean daily TS and FS intakes and frequency were calculated, and consumption patterns from foods and meals are presented. The proportion of foods that were covered or non-covered by the GUI SFQ was calculated by comparison with the NPNS food diary.

Results
75% of 3 year-olds had FS intake greater than the maximum recommended by WHO guidelines for free sugar intake, while 4% met the lower threshold. The median frequency of TS and FS consumption was 5.0 (4.0–6.0) and 4.0 (3.0–5.0) times/day. Less than one-quarter of TS intake (g/day) was non-covered by the GUI SFQ while less than one-third of FS intake was non-covered.

Conclusions
A large majority of 3-year-old Irish children do not meet the WHO recommended guidelines for FS intake and almost none meet the desired conditional recommendation. SFQs only capture two-thirds of FS intake at this early age.

Purposes
Dietary free sugars (FS) are the most important risk factor for dental caries and can contribute to excess energy intake. Measuring FS intake is limited by food composition databases and appropriate dietary assessment methods. The aim of this analysis was to estimate total sugar (TS) and FS intakes for Irish pre-schoolers and examine the proportion of dietary TS and FS captured using a short food questionnaire (SFQ).

Methods
This is a secondary analysis of 3-year-old children from two national surveys; Growing Up in Ireland (GUI), N = 9793 of whom 49% were girls and the National Preschool Nutrition Survey (NPNS), N = 126 and 52% were girls. GUI used SFQs and NPNS used semi-weighed food diaries to collect dietary data from 3-year-old children. Dietary intake databases were linked using an established approach. Mean daily TS and FS intakes and frequency were calculated, and consumption patterns from foods and meals are presented. The proportion of foods that were covered or non-covered by the GUI SFQ was calculated by comparison with the NPNS food diary.

Results
75% of 3 year-olds had FS intake greater than the maximum recommended by WHO guidelines for free sugar intake, while 4% met the lower threshold. The median frequency of TS and FS consumption was 5.0 (4.0–6.0) and 4.0 (3.0–5.0) times/day. Less than one-quarter of TS intake (g/day) was non-covered by the GUI SFQ while less than one-third of FS intake was non-covered.

Conclusions
A large majority of 3-year-old Irish children do not meet the WHO recommended guidelines for FS intake and almost none meet the desired conditional recommendation. SFQs only capture two-thirds of FS intake at this early age.

A growing number of international studies document the importance of regular school attendance. There is a consensus among authors that absenteeism has negative implications for academic achievement as well as the social development of the child and may put them at a disadvantage in terms of their position in the education and labour market. Most of the existing studies have focused on school absenteeism among adolescents with studies on poor school attendance among young children relatively rare. This paper addresses this gap in research by exploring factors that are related to school absenteeism in Irish primary schools. Drawing on a nationally representative study of nine-year-olds, it demonstrates the complexity of the issue. The findings indicate that a combination of institutional and individual factors shape patterns of poor school attendance in Irish primary schools. While the data relate to the Irish situation, the paper raises a number of issues of interest to an international audience.

Keywords
school absenteeism, primary schools, national survey, Ireland

A large body of international literature has documented a correlation between nontraditional family structure and poorer child outcomes, yet researchers continue to disagree as to whether the association represents a true causal effect. This article extends this literature by employing propensity score matching using the first wave of data from the Growing up in Ireland child cohort study. We argue that the Irish case is of particular interest given the highly selective nature of non-marriage. We find that, on average, non-marriage has negative effects on a child educational development at age 9 but the effects are smaller in relation to health outcomes and the child’s self-concept. However, selection effects account for a non-trivial proportion of the differences in child outcomes across lone-mother and cohabiting families although hidden bias remains an important issue. This has important implications for policies which promote marriage as the key to child development as it appears that much of the benefits of marriage are not related to marriage per se but to the socio-economic background of mothers.

A poor quality diet may be a common risk factor for both obesity and dental problems such as caries. The aim of this paper is to use classification tree analysis (CTA) to identify predictors of dental problems in a nationally representative cohort of Irish pre-school children. CTA was used to classify variables and describe interactions between multiple variables including socio-demographics, dietary intake, health-related behaviour, body mass index (BMI) and a dental problem. Data were derived from the second (2010/2011) wave of the ‘Growing Up in Ireland’ study (GUI) infant cohort at 3 years, n = 9793. The prevalence of dental problems was 5.0% (n = 493). The CTA model showed a sensitivity of 67% and specificity of 58.5% and overall correctly classified 59% of children. Ethnicity was the most significant predictor of dental problems followed by longstanding illness or disability, mother’s BMI and household income. The highest prevalence of dental problems was among children who were obese or underweight with a longstanding illness and an overweight mother. Frequency of intake of some foods showed interactions with the target variable. Results from this research highlight the interconnectedness of weight status, dental problems and general health and reinforce the importance of adopting a common risk factor approach when dealing with prevention of these diseases.

Keywords: body mass index; diet; dental problem; classification tree

A recent rise in home computer ownership has seen a growing number of children using computers and accessing the internet from a younger age. This paper examines the link between children’s home computing and their academic performance in the areas of reading and mathematics. Data from the nine-year-old cohort of the Growing Up in Ireland survey is adopted for this study. The survey reveals that searching for information is a more popular activity among the children than communicating online. Through regression analysis we find that using a computer is positively and significantly associated with children’s reading and mathematics scores in standardised tests. This result holds after controlling for multiple determinants of school performance. In addition, we investigate the effects of using various applications on the computer. Surfing the internet for fun, doing projects for school and emailing are associated with higher reading and maths test scores, while those who are permitted to use the computer unsupervised tend to have higher maths test scores. Instant messaging and downloading music or watching movies are negatively associated with both reading and maths scores. The results indicate that some forms of early computer use have significant associations with academic performance among children in primary school, although we could not establish the direction of causation definitively.

Keywords: home computer use, elementary education, academic performance