External Publications Using GUI Data

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.

Importance As young people’s mental health difficulties increase, understanding risk and resilience factors under challenging circumstances becomes critical.

Objective To explore the outcomes of the COVID-19 pandemic on secondary school students’ mental health difficulties, as well as the associations with individual, family, friendship, and school characteristics.

Design, Setting, and Participants For this cohort study, follow-up data from the My Resilience in Adolescence (MYRIAD) cluster randomized clinical trial were collected across 2 representative UK cohorts. Mainstream UK secondary schools with a strategy and structure to deliver social-emotional learning, with an appointed head teacher, and that were not rated “inadequate” in their latest official inspection were recruited. A total of 5663 schools were approached, 532 showed interest, and 84 consented. Cohort 1 included 12 schools and 864 students, and cohort 2 included 72 schools and 6386 students. COVID-19 was declared a pandemic after cohort 1 had completed all assessments (September 2018 to January 2020), but cohort 2 had not (September 2019 to June 2021).

Exposures Cohort 2 was exposed to the COVID-19 pandemic, including 3 national lockdowns. Associations of individual, family, friendship, and school characteristics with students’ mental health were explored.

Main Outcomes and Measures Changes in students’ risk for depression (Center for Epidemiological Studies-Depression scale); social, emotional, and behavioral difficulties (Strengths and Difficulties Questionnaire); and mental well-being (Warwick-Edinburgh Mental Well-Being Scale).

Results Of the 7250 participants included, the mean (SD) age was 13.7 (0.6) years, 3947 (55.4%) identified as female, and 5378 (73.1%) self-reported their race as White. Twelve schools and 769 of the 864 students (89.0%) in cohort 1 and 54 schools and 2958 of the 6386 students (46.3%) in cohort 2 provided data and were analyzed. Mental health difficulties increased in both cohorts but to a greater extent among students exposed to the pandemic, including for risk of depression (adjusted mean difference [AMD], 1.91; 95% CI, 1.07-2.76); social, emotional, and behavioral difficulties (AMD, 0.76; 95% CI, 0.33-1.18); and mental well-being (AMD, −2.08; 95% CI, −2.80 to −1.36). Positive school climate, high home connectedness, and having a friend during lockdown were protective factors during the pandemic. Female gender and initial low risk for mental health difficulties were associated with greater mental health deteriorations. Partial school attendance during lockdown was associated with better adjustment than no attendance when returning to school.

Conclusions and Relevance This cohort study of secondary school students demonstrated that to promote mental health and adjustment, policy interventions should foster home connectedness, peer friendship, and school climate; avoid full school closures; and consider individual differences.

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.

Objective
Childhood chronic illness can have a high impact on the child’s quality of life. The foundations of health are established in early life, and are shaped by biological, psychosocial, spiritual and environmental processes and influences. The objectives of this presentation are twofold: firstly to describe the prevalence of chronic illness in 9-year-olds in Ireland, secondly to illustrate how chronic illness influences the psychological and social development of the children.

Methods
Analysis was based on data of 8570 9-year old children, and their families who participated in Growing Up in Ireland—the National Longitudinal Study of Children. The sample was generated through the primary school system. A representative sample of 910 schools participated; the sample of children and their families was randomly selected from within the schools. Questionnaires were administered in schools; and after completion of this phase, the project interviewers visited the families of the 9-year olds in their homes and administered core questionnaires to the Study Child and his/her carers who provided either home-based or centre-based care on a regular basis.

Results
The overall prevalence of chronic illness reported by mothers among the 9-year old cohort was 11% (gender-specific prevalence for boys: 13%, and significantly lower for girls: 10%). Respiratory illnesses accounted for almost half (46%) of all chronic illnesses, followed by mental and behavioural conditions with 19% (high gender dysbalance: reported for boys in 24%, for girls in 12%). Children with a reported chronic illness had significantly more emotional, conduct, hyperactivity, peer-based and prosocial difficulties when compared with children without a reported chronic illness. Abnormal scores, based on the Strengths and Difficulties Questionnaire were found in 20% in children with a chronic disease, and in 5.5% in children without a chronic disease. Socio-economic Status was associated with poorer health outcomes. Furthermore, primary care givers’ views and perceptions regarding the chronic illness of the child were found to be a significant factor on child strengths and difficulties in a multivariate model.

Conclusions
The majority of 9-year old children can be assessed as healthy. The most common chronic illness in this large cohort was respiratory disease and overall, chronic conditions were found to have a negative impact on the child’s emotional and social state.

Background
Historically, breastfeeding rates in Ireland have been low compared with international averages. It has been suggested that maternal ethnicity and citizenship may influence breastfeeding rates, with ethnic minorities thought more likely to breast feed.

Aim
The aim of this study is to investigate the association among maternal citizenship, ethnicity, birthplace and breast feeding. It is hypothesised that Irish mothers (identified through Irish citizenship, self-identified Irish ethnicity or Irish birthplace) are less likely to breast feed than non-Irish mothers.

Methods
The study population of Growing Up in Ireland: the National Longitudinal Study of Children was used for this study. Analysis was restricted to 11 092 biological mother and infant pairs with a complete breastfeeding history. Logistic regression analysis was used to estimate ORs and 95% CIs for breast feeding relative to maternal citizenship and ethnicity, controlling for the confounding effects of other maternal variables.

Results
Results indicated that 55.9% (6202 of 11 092) of mothers had initiated breast feeding, with only 7.9% (874 of 11 092) of mothers currently breast feeding their infant (at 9 months of age). Irish citizens (4693 of 9368, 50.0%) were significantly less likely to have initiated breast feeding compared with non-Irish citizens (1503 of 1695, 88.7%). Irish born mothers (4179 of 8627, 48.8%) were also significantly less likely to have initiated breast feeding than mothers born elsewhere (2023 of 2462, 82.2%).

Conclusions
Maternal citizenship and ethnicity appear to be the strongest influencing factors on breastfeeding initiation and duration. However, this raises a possibility that the increase in breastfeeding rates seen recently may be the result of increased immigration into Ireland, rather than the success of policy and research efforts.

Background
Globally, childhood obesity is a significant public health problem associated with adverse health and economic consequences. To tackle the problem, we need a comprehensive understanding on how the environment in which we live may influence obesity related behaviours and weight status. Thus, we explore if distance to and number of food outlets ([1] supermarkets and [2] convenience stores) in the local area impact on either dietary quality or body mass index (BMI) in 9-year-old children whilst controlling for socio-economic characteristics of the family.

Methods
Cross sectional analysis of the Growing Up in Ireland (GUI) Study, a two-stage clustered sample of 8568 nine year old children from the Republic of Ireland. Children were recruited from schools (response rate 82%) and age eligible children (response rate 57%) were invited to participate. Height and weight measurements were used to calculate BMI. Diet was assessed using a short food frequency questionnaire and a dietary quality score was generated based on Irish healthy eating guidelines. Socio-economic status was measured using parent reported household class, household net equivalised income and highest level of maternal education. Food access was measured as network distance to (in quintiles) and number of (within 1000km) convenience stores and supermarkets to each participant’s household within the local area. Separate fixed effects regression models were used to assess the impact of local area food access on (1) dietary quality and (2) BMI, stratified by gender.

Results
After controlling for socio-economic characteristics of the household, distance to the nearest supermarket was not associated with dietary quality in boys (Q5 v Q1; B = 0.84, 95% CI, –0.49 to 2.18) or girls (Q5 v Q1; B = –0.41, 95% CI, –1.60 to 0.77). Distance to the nearest convenience store was associated with dietary quality in boys (Q5 v Q1; B = 1.01, 95% CI, 0.13 to 1.89) but not in girls (Q5 v Q1; B = 0.04, 95% CI, –0.71 to 0.80). The number of convenience stores or supermarkets within 1000m of the household did not impact on dietary quality. Access to food outlets was not associated with BMI in girls or boys.

Conclusion
There was little evidence to suggest that access to food stores impact dietary quality or BMI in children. From a population health perspective, strategies tackling environmental factors associated with making poor lifestyle choices are needed. Thus, further research on the association between food access and obesity risk is needed.

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.

Background
Independent associations between screen time (ST)/physical activity (PA) and overweight (OW)/obesity have been demonstrated but little research exists on the role of ST among sufficiently active children.

Purpose
To examine the combined influence of ST and PA on risk of OW/obesity in a nationally representative sample of 9-year-old Irish children.

Methods
The sample in this cross sectional analysis contained 8568 children. Self-report parent data were used to group children into ST and PA categories and related to OW/obesity using forced entry logistic regression.

Results
High ST (> 3 hours/day), bedroom TV and mobile phone ownership increased risk of OW/obesity in high and low active children (P < .05). Low PA (<9 bouts fortnightly) was also associated with OW/obesity. In combined analyses, OW/obesity was lowest in the reference low ST/high PA group with ORs of 1.38, 1.63, and 2.07, respectively, in the low ST/low PA, high ST/high PA, and high ST/low PA groups. Access to electronic media, low socioeconomic status, parental obesity, and not engaging in sports were all related to high ST (P < .05).

Conclusion
This study supports findings that ST is associated with OW/Obesity demonstrating this separately in high and low active children.

Background
The aim of this study was to use a social-ecological approach to examine the influence of individual, social, and environmental factors on moderate-to-vigorous physical activity (MVPA) and screen-time in a sample of 9-year-old children in Ireland.

Methods
The sample was 1509 boys and girls from the Growing Up in Ireland (GUI) national study. MVPA, screen time, and individual, social, and environmental variables were assessed via questionnaires completed by children, their parents, and their teachers. Multiple regression was used to identify factors that correlated with children’s MVPA and screen-time levels.

Results
For boys, factors such as activity with friends (P < .0001) and popularity (P < .01) were associated with MVPA, while factors such as BMI (P < .01) and MVPA (P < .01) were associated with screen time. Similarly for girls, factors such as activity with friends (P < .0001) and sociability were associated with MVPA, however factors such as BMI (P < .05), and access to play space (P < .05) were more closely associated with screen time.

Conclusion
Social factors were more closely associated with MVPA, while individual factors were significantly correlated with screen time for both boys and girls. Correlates differed for boys and girls, suggesting that interventions should consider both the target population as well as the activity behavior.

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.

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

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

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

Background
Population-based studies provide important data to inform policy and service planning for vulnerable children in society. The aim of this study was to characterise social and educational circumstances and self-concept among a nationally representative sample of 13 year olds with developmental disabilities in Ireland.

Methods
A cross-sectional, secondary analysis of data collected from the Growing Up in Ireland (GUI) study was conducted. Descriptive statistics were used to calculate the reported prevalence of disabilities as reported by parents. Differences across the groups (those with and without disabilities) were analysed in relation to gender, socio-economic and school factors. Special education support received in school was described. The association between low self-concept scores (as measured by the Piers Harris Self-Concept Scales 2) and disability type was examined by use of multi-level logistic regression.

Results
Seventeen percent (17.36%) of the sample was reported to have a diagnosis of one or more developmental disabilities. Those with a disability were more likely to live in poorer households, have poorer health status, to experience more episodes of bullying at school, and to have more negative views of school (p<0.05) than their typically-developing peers.

Forty nine percent of children with developmental disabilities were not receiving support in school as reported by parents. Discrepancies in the nature of support received were identified across disability types. Adjusting for individual and school level factors, a disability diagnosis was associated with increased odds of low self-concept scores on three of five self-concept domains. Further associations were identified which differed across disability type.

Conclusions
The findings show that 13 year olds with a disability in Ireland have complex social and educational needs. Findings also suggest significant levels of unmet educational need across this age group. Apparent inequities in access to support in school require further investigation. Reliable measures to provide robust prevalence figures about childhood disabilities in Ireland are needed.

Background
The Covid pandemic arrived in Ireland on February 29, 2020. In the following weeks various restrictions were introduced to stem the spread of the disease. Anxiety over the spread of the disease and over the restrictions introduced had an adverse effect upon mental health. This study examines the change in mental health for two groups: young adults aged around 23 at the time of onset of Covid (the 1998 cohort) and a sample of principal carers (PCs) of children who were aged 13 at the onset of Covid (the 2008 cohort).

Methods
Data were obtained from the two cohorts of the longitudinal Growing Up In Ireland (GUI) survey. The sample included 1953 young adults (from the 1998 cohort) and 3547 principal carers (from the 2008 cohort). Mental health as measured by the Centre for Epidemiological Studies Depression—8 scale was obtained for the last pre-Covid wave and for the Covid wave (surveyed in December 2020). Observations for which CES-D8 was not available in either pre or post Covid waves were excluded. Post-Covid sampling weights were applied. The change in depression rates was decomposed into a growth and distribution effect using a Shapley decomposition. The socioeconomic gradient of CES-D8 was examined pre and post Covid using concentration indices and a transition matrix was constructed to examine the dynamics of changes in CES-D8 and depression pre and post-Covid.

Results
Relative to the last pre-Covid survey, mental health, as measured by CES-D8 deteriorated for both the young adults of the 1998 cohort and the PCs of the 2008 cohort. For young adults, the deterioration was more pronounced for females. There was no observable socioeconomic gradient for poor mental health amongst young adults, both pre and post Covid. For mothers from the 2008 cohort, a gradient was observed during the pre-COVID-19 pandemic period with poorer mental health status for lower-income and less educated mothers. This gradient was less pronounced post-Covid, the levelling-off arising from a greater deterioration in mental health for higher-income and better-educated PCs.

Conclusion
Both observed cohorts showed a significant deterioration in mental health post Covid. For young adults the effect was significantly more pronounced among females and this is consistent with generally poorer mental health amongst females in this age group. There was little or no socioeconomic gradient observed for young adults, but the gradient became more shallow for principal carers. Care must be taken in terms of drawing policy implications from this study as the Covid-19 pandemic was arguably a unique event, even allowing for the likelihood of future pandemics. However, the study highlights the vulnerability of young adults, especially females, to the mental health effects arising from major public health shocks.

This article uses two longitudinal cohort studies (Growing Up in Ireland and the National Educational Panel Study) to examine how shadow education relates to academic performance in Ireland and Germany. Patterns of take-up of, and outcomes from, shadow education are found to reflect the particular country context—aimed at maintaining performance to avoid grade retention in Germany and preparing for a high-stakes upper secondary exam in Ireland. Participation enhances academic performance but only for students with lower levels of prior achievement. However, the relationship is not much stronger than with engagement in structured out-of-school activities. Thus, shadow education appears to be one of a number of strategies used by more privileged families to secure educational advantage.

To date, studies using cross-sectional methodologies make up a majority of the literature surrounding children with autism spectrum disorders and participation in physical activity and screen time. Longitudinal studies are needed to examine how physical activity and screen time behaviors co-develop for children with and without an autism spectrum disorder. To address this research gap, this study compared how physical activity and screen time levels changed over time (9 to 18 years of age) between youth with autism spectrum disorder and youth with neurotypical development. Data on the levels of moderate-to-vigorous physical activity, light physical activity, television-, and video game-based screen time, collected as a part of the “Growing up in Ireland” study, were compared between youth with autism spectrum disorder and a propensity-matched sample of youth with neurotypical development (n = 88 per group; 176 in total). Robust regression analyses indicated that children with autism spectrum disorder became less active over time compared to children with neurotypical development and that video game screen time also differed significantly between the groups when children were 9 years old. These findings elucidate important disparities present between these groups of children during pivotal developmental times.

Investigations into the wider bioecological understanding of dental problems in early childhood are limited in national surveys. Classification tree analysis (CTA) was used to explore multilevel interactions among key aspects of child and primary caregiver (PCG) psychosocial and physical health affecting dental problems in preschool children. Data were derived from the Growing Up in Ireland study, a nationally representative sample of 9-mo-olds (N = 11,134) in 2007/2008 followed up at age 3 y (N = 9,793) in 2010/2011. Analysis included PCG reports of children’s dental problems, general health, temperament, emotional and behavioral difficulties, and their own general health, stress and depression, relationship, and sociodemographic variables. Misclassification costs were specified for the model by applying a higher penalty for misclassifying those with a dental problem (minority class). Logistic regression analyses were carried out for comparison. Dental problems were reported among 302 infants (2.7%) at 9 mo of age and 493 children (5.0%) at 3 y. CTA identified infant temperament (Infant Characteristics Questionnaire unpredictable) as the primary predictor of dental problems at 9 mo and child global health at 3 y of age. First-level predictors were PCG depression score and use of a soother at 9 mo and PCG ethnicity and unscheduled hospital visits at 3 y of age. Regression analyses results supported the most important predictors at 9 mo and 3 y of age. The CTA model for 9-mo-old infants had a specificity of 90.4%, sensitivity of 31.2%, and overall accuracy of 88.8% while that for 3-y-olds had a specificity of 58.5%, sensitivity of 66%, and overall accuracy of 59%. Key aspects of infant/child and PCG health, as well as psychosocial characteristics associated with reported dental problems, should be considered in future multidisciplinary approaches to child health.

Knowledge Transfer Statement: The results of this data analysis should help raise awareness among clinicians of how primary caregiver and child psychosocial and general health factors are associated with early childhood dental problems, even before the primary dentition is complete. Classification tree analysis visually demonstrates how factors such as infant temperament (9 mo) and child global health (3 y) can interact at multiple levels and affect different subgroups of the child population. Future intervention strategies for oral health should involve consideration of the psychological and general health characteristics of the young child and PCG at both the patient and population levels. This knowledge could assist decision makers adopt an integrated multidisciplinary approach in formulating a coherent oral health policy for preschool children.