Household income supplements in early childhood to reduce inequities in children's development.

BACKGROUND: Early childhood interventions have the potential to reduce children's developmental inequities. We aimed to estimate the extent to which household income supplements for lower-income families in early childhood could close the gap in children's developmental outcomes and parental mental health. METHODS: Data were drawn from a nationally representative birth cohort, the Longitudinal Study of Australian Children (N = 5107), which commenced in 2004 and conducted follow-ups every two years. Exposure was annual household income (0-1 year). Outcomes were children's developmental outcomes, specifically social-emotional, physical functioning, and learning (bottom 15% versus top 85%) at 4-5 years, and an intermediate outcome, parental mental health (poor versus good) at 2-3 years. We modelled hypothetical interventions that provided a fixed-income supplement to lower-income families with a child aged 0-1 year. Considering varying eligibility scenarios and amounts motivated by actual policies in the Australian context, we estimated the risk of poor outcomes for eligible families under no intervention and the hypothetical intervention using marginal structural models. The reduction in risk under intervention relative to no intervention was estimated. RESULTS: A single hypothetical supplement of AU$26,000 (equivalent to ∼USD$17,350) provided to lower-income families (below AU$56,137 (∼USD$37,915) per annum) in a child's first year of life demonstrated an absolute reduction of 2.7%, 1.9% and 2.6% in the risk of poor social-emotional, physical functioning and learning outcomes in children, respectively (equivalent to relative reductions of 12%, 10% and 11%, respectively). The absolute reduction in risk of poor mental health in eligible parents was 1.0%, equivalent to a relative reduction of 7%. Benefits were similar across other income thresholds used to assess eligibility (range, AU$73,329-$99,864). CONCLUSIONS: Household income supplements provided to lower-income families may benefit children's development and parental mental health. This intervention should be considered within a social-ecological approach by stacking complementary interventions to eliminate developmental inequities.

The potential of intervening on childhood adversity to reduce socioeconomic inequities in body mass index and inflammation among Australian and UK children: A causal mediation analysis.

BACKGROUND: Lower maternal education is associated with higher body mass index (BMI) and higher chronic inflammation in offspring. Childhood adversity potentially mediates these associations. We examined the extent to which addressing childhood adversity could reduce socioeconomic inequities in these outcomes. METHODS: We analysed data from two early-life longitudinal cohorts: the Longitudinal Study of Australian Children (LSAC; n=1873) and the UK Avon Longitudinal Study of Parents and Children (ALSPAC; n=7085). EXPOSURE: low/medium (below university degree) versus high maternal education, as a key indicator of family socioeconomic position (0-1 year). OUTCOMES: BMI and log-transformed glycoprotein acetyls (GlycA) (LSAC: 11-12 years; ALSPAC: 15.5 years). Mediator: multiple adversities (≥2/<2) indicated by family violence, mental illness, substance abuse and harsh parenting (LSAC: 2-11 years; ALSPAC: 1-12 years). A causal mediation analysis was conducted. RESULTS: Low/medium maternal education was associated with up to 1.03 kg/m2 higher BMI (95% CI: 0.95 to 1.10) and up to 1.69% higher GlycA (95% CI: 1.68 to 1.71) compared with high maternal education, adjusting for confounders. Causal mediation analysis estimated that decreasing the levels of multiple adversities in children with low/medium maternal education to be like their high maternal education peers could reduce BMI inequalities by up to 1.8% and up to 3.3% in GlycA. CONCLUSIONS: Our findings in both cohorts suggest that slight reductions in socioeconomic inequities in children's BMI and inflammation could be achieved by addressing childhood adversities. Public health and social policy efforts should help those affected by childhood adversity, but also consider underlying socioeconomic conditions that drive health inequities.

Developmental relationships between socio-economic disadvantage and mental health across the first 30 years of life.

Understanding of how socio-economic disadvantage experienced over the life course relates to mental health outcomes in young adulthood has been limited by a lack of long-term, prospective studies. Here we address this limitation by drawing on data from a large Australian population cohort study that has followed the development of more than 2,000 Australians (and their families) from infancy to young adulthood since 1983. Associations were examined between prospective assessments of socio-economic position (SEP) from 4-8 months to 27-28 years and mental health problems (depression, anxiety, stress) and competence (civic engagement, emotional maturity, secure intimate relationship) at 27-28 years. The odds of being socio-economically disadvantaged in young adulthood were elevated eight- to tenfold in those who had experienced disadvantage in the family of origin, compared with those who had not (OR 8.1, 95% CI 4.5-14.5 to 10.1, 95% CI 5.2-19.5). Only concurrent SEP was associated with young adult mental health problems, and this effect was limited to anxiety symptoms (OR 2.0, 95% CI 1.1-3.9). In contrast, SEP had more pervasive impacts on young adult competence, particularly in the civic domain where effects were evident even from early infancy (OR 0.46, 95% CI 0.26-0.81). Findings suggest that one potentially important mechanism through which disadvantage compromises mental health is through limiting the development and consolidation of key psychosocial competencies needed for health and well-being in adulthood.

Inequalities in the distribution of COVID-19-related financial difficulties for Australian families with young children.

BACKGROUND: We examine (1) the frequency of financial difficulties in Australian families with young children (0-8 years) in the early and later phases of the pandemic; (2) the extent to which parents' pre-pandemic socio-economic disadvantage (SED) predicted financial difficulties; and (3) whether grandparent intergenerational SED further amplified this risk. METHOD: Data: Australian Temperament Project (ATP; established 1983, N = 2443) and ATP Generation 3 study (ATPG3; established 2012; N = 702), of which 74% (N = 553) completed a COVID-specific module in the early (May-September 2020) and/or later (October-December 2021) phases of the pandemic. OUTCOMES: Parent-reported loss of employment/reduced income, difficulty paying for essentials, and financial strain. EXPOSURES: Pre-pandemic parent and grandparent education and occupation. ANALYSIS: Logistic regressions, estimated via generalized estimating equations, were used to examine associations between the pre-pandemic SED of parents and grandparents and their interaction with financial difficulties, adjusting for potential confounders. RESULTS: At both pandemic time points, a third of parents reported adverse financial impacts (early: 34%, 95% confidence interval [CI] = 30-38; later: 32%, 95% CI = 28-36). Each standard deviation increase in the parents' pre-pandemic SED was associated with a 36% increase in the odds of reporting multiple financial difficulties (odds ratio [OR] = 1.36, 95% CI = 1.04-1.78). There was little evidence of an interaction between the SED of parents and grandparents. CONCLUSIONS: Financial impacts related to the COVID-19 pandemic were common and, irrespective of grandparent SED, disproportionately borne by parents with higher pre-pandemic SED. Given the well-established relationship between disadvantage and child health and development, sustained and well-targeted government supports will be critical to minimizing adverse impacts in years to come.

Natural history of mental health competence from childhood to adolescence.

BACKGROUND: Mental health competence (MHC) involves psychosocial capabilities such as regulating emotions, interacting well with peers and caring for others, and predicts a range of health and social outcomes. This study examines the course of MHC from childhood to adolescence and patterning by gender and disadvantage, in Australian and UK contexts. METHODS: Data: Longitudinal Study of Australian Children (n=4983) and the Millennium Cohort Study (n=18 296). Measures: A measure capturing key aspects of MHC was derived summing items from the parent-reported Strengths and Difficulties Questionnaire, assessed at 4-5 years, 6-7 years, 10-11 years and 14-15 years. Analysis: Proportions of children with high MHC (scores ≥23 of range 8-24) were estimated by age and country. Random-effects models were used to define MHC trajectories according to baseline MHC and change over time. Sociodemographic patterns were described. RESULTS: The prevalence of high MHC steadily increased from 4 years to 15 years (from 13.6% to 15.8% and 20.6% to 26.2% in Australia and the UK, respectively). Examination of trajectories revealed that pathways of some children diverge from this normative MHC progression. For example, 7% and 9% of children in Australia and the UK, respectively, had a low starting point and decreased further in MHC by mid-adolescence. At all ages, and over time, MHC was lower for boys compared with girls and for children from disadvantaged compared with advantaged family backgrounds. CONCLUSIONS: Approaches to promoting MHC require a sustained focus from the early years through to adolescence, with more intensive approaches likely needed to support disadvantaged groups and boys.

Inequities in Children's Reading Skills: The Role of Home Reading and Preschool Attendance.

OBJECTIVE: Children from socioeconomically disadvantaged backgrounds have poorer learning outcomes. These inequities are a significant public health issue, tracking forward to adverse health outcomes in adulthood. We examined the potential to reduce socioeconomic gaps in children's reading skills through increasing home reading and preschool attendance among disadvantaged children. METHODS: We drew on data from the nationally representative birth cohort of the Longitudinal Study of Australian Children (N = 5107) to examine the impact of socioeconomic disadvantage (0-1 year) on children's reading skills (8-9 years). An interventional effects approach was applied to estimate the extent to which improving the levels of home reading (2-5 years) and preschool attendance (4-5 years) of socioeconomically disadvantaged children to be commensurate with their advantaged peers, could potentially reduce socioeconomic gaps in children's reading skills. RESULTS: Socioeconomically disadvantaged children had a higher risk of poor reading outcomes compared to more advantaged peers: absolute risk difference = 20.1% (95% confidence interval [CI]: 16.0%-24.2%). Results suggest that improving disadvantaged children's home reading and preschool attendance to the level of their advantaged peers could eliminate 6.5% and 2.1% of socioeconomic gaps in reading skills, respectively. However, large socioeconomic gaps would remain, with disadvantaged children maintaining an 18.3% (95% CI: 14.0%-22.7%) higher risk of poor reading outcomes in absolute terms. CONCLUSION: There are clear socioeconomic disparities in children's reading skills by late childhood. Findings suggest that interventions that improve home reading and preschool attendance may contribute to reducing these inequities, but alone are unlikely to be sufficient to close the equity gap.

A Novel 3-Part Approach to Tackle the Problem of Health Inequities in Early Childhood.

The first 5 years of a child's life are crucial in laying the foundation for their health and developmental trajectory into adulthood. These early years are especially influenced by the surrounding environments in which children live and grow. A large international body of evidence demonstrates that children who experience disadvantage tend to fall increasingly behind over time. At the societal level, these inequities can cause substantial social burdens and significant costs across health, education, and welfare budgets. A contributing factor is that children experiencing adversity are less likely to have access to the environmental conditions that support them to thrive. Many of these factors are modifiable at the community or place level. We argue for three key-though not exhaustive-ideas that collectively could achieve more equitable outcomes for children facing disadvantage and experiencing adversity:We conclude that if adopted, these 3 ideas could contribute to the ability of local communities and networks to identify and respond to factors that address early childhood inequalities.

Health service utilisation and unmet healthcare needs of Australian children from immigrant families: A population-based cohort study.

Compared with most other Organization for Economic Co-operation and Development (OECD) countries, information about the patterns of health service use for children from immigrant families in Australia is currently limited, and internationally, data on unmet healthcare needs are scarce. This study aims to examine the distribution of health service utilisation and unmet healthcare needs for immigrant children aged 10-11 years in Australia. We drew on data from the Longitudinal Study of Australian Children Birth (B; n = 5,107) and Kindergarten (K; n = 4,983) cohorts. The exposure was family immigration background collected at 0-1 (B-cohort) and 4-5 (K-cohort) years. Outcomes were parent-reported child health service use and unmet healthcare needs (defined as the difference between services needed and services received) at 10-11 years. Logistic regression analyses were used to examine associations between family immigration background and health service use/unmet healthcare needs, adjusting for potential confounders. Results showed that one-third of Australian children (B-cohort: 29.0%; K-cohort: 33.4%) came from immigrant families. There were similar patterns of health service use and unmet healthcare needs between children from English-speaking immigrant and Australian-born families. However, children from non-English-speaking immigrant families used fewer health services, including paediatric, dental, mental health and emergency ward services. There was a disparity between the services used when considering children's health needs, particularly for paediatric specialist services (B-cohort: OR = 2.43, 95% CI 1.11-5.31; K-cohort: OR = 2.72, 95% CI 1.32-5.58). Findings indicate that Australian children from non-English-speaking immigrant families experience more unmet healthcare needs and face more barriers in accessing health services. Further effort is needed to ensure that the healthcare system meets the needs of all families.

Better support for children with additional health and developmental needs in school settings: Perspectives of education experts.

AIM: Many children start school with additional health and developmental needs (AHDN), yet how best to support these children for optimal outcomes in the school setting is a complex challenge. This study aims to determine the views of education experts on what differentiates the most effective primary schools. METHODS: Qualitative interviews were conducted with nine senior leaders across the education system responsible for managing or improving practice across a range of schools or school regions in Victoria. Using a positive deviance approach, which investigates strategies already implemented in organizations achieving desired outcomes, the semi-structured interviews aimed to elicit instances of perceived good practice that already exists within the school system. Interviews were analysed using inductive content analysis. RESULTS: All education experts reported high variability across schools and suggested a number of factors differentiating those that were most effective at supporting children with AHDN. They included the presence of strong teacher support by the school leadership team; explicit and documented processes to guide the practice of teachers and ensure consistency at a whole school level; inclusive relationships and environments; participation and knowledge sharing between medical, allied health and other stakeholders in the care team; and an evidenced-based approach to allocating resources to programmes and strategies. CONCLUSION: This exploration of instances of good practice can generate novel insights into a complex problem. Current findings suggest a number of potential opportunities for enhancing practice that can be tested in future research. Improving outcomes for this vulnerable and significant group of children will require collaboration across health and education.

Use of health services by preschool-aged children who are developmentally vulnerable and socioeconomically disadvantaged: testing the inverse care law.

AIM: The inverse care law suggests that those with the greatest need for services are least likely to receive them. Our aim of this study was to test the inverse care law in relation to the use of health services by children aged 4-5 years in Australia who were developmentally vulnerable and socioeconomically disadvantaged. METHOD: Cross-sectional data were collected from the Longitudinal Study of Australian Children birth cohort when the children were aged 4-5 years. Children were grouped according to the combination of developmental vulnerability (yes, no) and socioeconomic disadvantage (lower, higher), resulting in four groups (reference group: developmentally vulnerable and disadvantaged). Multivariate regression was used to examine the impact of the combination of developmental vulnerability and disadvantage on health service use, adjusting for other sociodemographic characteristics. RESULTS: 3967 (90%) of children had data on developmental vulnerability at 4-5 years. A third of children (32.6%) were classified as developmentally vulnerable, and 10%-25% of these children had used health services. Non-disadvantaged children who were developmentally vulnerable (middle need) had 1.4-2.0 times greater odds of using primary healthcare, specialist and hospital services; and non-disadvantaged children who were not developmentally vulnerable (lowest need) had 1.6-1.8 times greater odds of using primary healthcare services, compared with children who were developmentally vulnerable and disadvantaged (highest need). CONCLUSION: We found some evidence of the inverse care law. Equity in service delivery remains a challenge that is critically important to tackle in ensuring a healthy start for children.

Learning outcomes of children with teacher-identified emerging health and developmental needs.

OBJECTIVES: Children's additional health and developmental needs are often first identified by teachers when they begin school. This study estimates the Grade 3 literacy and numeracy outcomes of children with teacher-identified additional needs emerging in the first year of school, including the added burden conferred by socioeconomic disadvantage. METHODS: Population linked data (n = 42,619) were analysed from the Australian Early Development Census, which include teacher reports on children's health and development at school entry, and the National Assessment Program-Literacy and Numeracy, a direct assessment of reading and numeracy skills at Grade 3. Linear regression analyses were used to estimate associations between emerging needs and learning outcomes, adjusted for sociodemographic characteristics. The combined effect of emerging needs and low maternal education (an indicator of socioeconomic disadvantage) on academic outcomes was examined by estimating the relative excess risk due to interaction (RERI). RESULTS: Emerging health and developmental needs at school entry were associated with lower reading (b = -26.86, 95% CI = -29.19, -24.52) and numeracy (b = -24.39, 95% CI = -26.43, -22.35) outcomes at Grade 3. The combined effect of emerging needs and socioeconomic disadvantage was greater than expected when their individual effects are summed (RERI = 0.38, 95% CI 0.22, 0.55 for reading and RERI = 0.27, 95% CI 0.10, 0.43 for numeracy). CONCLUSION: In the current study, emerging health and developmental needs identified by teachers at the outset of schooling were associated with poorer literacy and numeracy skills at Grade 3, and family socioeconomic disadvantage appeared to further amplify this effect. Meeting the needs of these children will require timely and coordinated supports across the health and education systems, particularly for those children who are also disadvantaged.

Inequalities in the Distribution of Childhood Adversity From Birth to 11 Years.

OBJECTIVE: Exposure to early adversity carries long term harmful consequences for children's health and development. This study aims to 1) estimate the prevalence of childhood adversity for Australian children from infancy to 10-11 years, and 2) document inequalities in the distribution of adversity according to socioeconomic position (SEP), Indigenous status, and ethnicity. METHODS: Adversity was assessed every 2 years from 0-1 to 10-11 years in the nationally representative birth cohort of the Longitudinal Study of Australian Children (N = 5107). Adversity included legal problems; family violence; household mental illness; household substance abuse; harsh parenting; parental separation/divorce; unsafe neighborhood; family member death; and bullying (from 4 to 5 years). Adversities were examined individually and summed for a measure of multiple adversity (2+ adverse experiences). RESULTS: By 10-11 years, 52.8% (95% confidence interval [CI] 51.0-54.7) of children had been exposed to 2 or more adversities. When combined with low SEP, children from ethnic minority and from Indigenous backgrounds had 4 to 8 times the odds of exposure to 2 or more adversities than children from higher SEP Anglo-Euro backgrounds, respectively (odds ratio [OR] 4.3, 95% CI 2.8-6.6 and OR 8.1, 95% CI 4.4-14.8). Ethnic minority and Indigenous children from higher SEP backgrounds had increased odds of exposure to multiple adversity than similarly advantaged Anglo-Euro children (OR 1.8, 95% CI 1.4-2.3 and OR 2.3, 95% CI 1.3-4.3, respectively). CONCLUSIONS: Addressing early adversity is a significant opportunity to promote health over the life course, and reduce health inequalities experienced by marginalized groups of children.

Potential of 'stacking' early childhood interventions to reduce inequities in learning outcomes.

BACKGROUND: Early childhood interventions are critical for reducing child health and development inequities. While most research focuses on the efficacy of single interventions, combining multiple evidence-based strategies over the early years of a child's life may yield greater impact. This study examined the association between exposure to a combination of five evidence-based services from 0 to 5 years on children's reading at 8-9 years. METHODS: Data from the nationally representative birth cohort (n=5107) of the Longitudinal Study of Australian Children were utilised. Risk and exposure measures across five services from 0 to 5 years were assessed: antenatal care, nurse home-visiting, early childhood education and care, parenting programme and the early years of school. Children's reading at 8-9 years was measured using a standardised direct assessment. Linear regression analyses examined the cumulative effect of five services on reading. Interaction terms were examined to determine if the relationship differed as a function of level of disadvantage. RESULTS: A cumulative benefit effect of participation in more services and a cumulative risk effect when exposed to more risks was found. Each additional service that the child attended was associated with an increase in reading scores (b=9.16, 95% CI=5.58 to 12.75). Conversely, each additional risk that the child was exposed to was associated with a decrease in reading skills (b=-14.03, 95% CI=-16.61 to -11.44). Effects were similar for disadvantaged and non-disadvantaged children. CONCLUSION: This study supports the potential value of 'stacking' early interventions across the early years of a child's life to maximise impacts on child outcomes.

Driving Precision Policy Responses to Child Health and Developmental Inequities.

The growing evidence base on the extent of and opportunities to reduce inequities in children's health and development still lacks the specificity to inform clear policy decisions. A new phase of research is needed that builds on contemporary directions in precision medicine to develop precision policy making; with the aim to redress child inequities. This would include identifying effective interventions and their ideal time point(s), duration, and intensity to maximize impact. Drawing on existing data sources and innovations in epidemiology and biostatistics would be key. The economic and social gains that could be achieved from reducing child inequities are immense.

Reducing Inequities in Early Childhood Mental Health: How Might the Neighborhood Built Environment Help Close the Gap? A Systematic Search and Critical Review.

BACKGROUND: Optimal mental health in early childhood is key to later mental health, physical health, education, and social outcomes; yet, children facing disadvantage tend to have worse mental health and fewer opportunities to develop this foundation. An emerging body of research shows that neighborhoods provide important opportunities for the development of children's mental health. Synthesizing this evidence can advance understandings of the features of the neighborhood built environment (e.g., housing, parks) that (1) promote optimal mental health in childhood and (2) reduce mental health inequities. METHODS: We systematically searched and critically reviewed the international quantitative literature investigating associations between the neighborhood built environment and young children's mental health. RESULTS: 14 articles met inclusion criteria; most examined nature or public open space. Studies tended to find greater access to or quantity of neighborhood nature or public open space were associated with better mental health. Significant gaps included a lack of studies investigating social infrastructure, and few studies examined how the built environment related to positive mental health (i.e., functioning, rather than problems). CONCLUSIONS: Current evidence suggests there is some relationship, but additional research is needed that addresses these gaps and examines differences in associations between child subgroups (e.g., diverse socioeconomic backgrounds).

Socioeconomic Disadvantage in Infancy and Academic and Self-Regulation Outcomes.

OBJECTIVES: A comprehensive understanding of how timing of exposure to disadvantage affects long-term developmental risk is needed for greater precision in child health policy. We investigated whether socioeconomic disadvantage in infancy (age 0-1 years) directly affects academic and self-regulation problems in late childhood (age 10-12 years), independent of disadvantage at school entry (age 4-6 years). METHODS: Analyses were replicated in 2 population-based cohorts: the Australian Temperament Project (ATP; N = 2443) and the Longitudinal Study of Australian Children (LSAC; N = 5107). Generalized linear models were used to estimate the crude and adjusted effects. Marginal structural models were used to estimate the controlled direct effect of socioeconomic disadvantage in infancy on academic and self-regulation outcomes in late childhood, independent of disadvantage at school entry. RESULTS: In both cohorts, socioeconomic disadvantage in infancy and at school entry was associated with poorer academic and self-regulation outcomes. Socioeconomic disadvantage in infancy had a direct effect on academic outcomes not mediated by disadvantage at school entry (ATP: risk ratio [RR] = 1.42; 95% confidence interval [CI]: 1.09-1.86; LSAC: RR = 1.87; 95% CI: 1.52-2.31). Little evidence was found for a direct effect of disadvantage in infancy on self-regulation (ATP: RR = 1.22; 95% CI: 0.89-1.65; LSAC: RR = 1.19; 95% CI: 0.95-1.49). CONCLUSIONS: Socioeconomic disadvantage in infancy had a direct effect on academic but not self-regulation outcomes in late childhood. More precise public policy responses are needed that consider both the timing of children's exposure to disadvantage and the specific developmental domain impacted.

Trends in the prevalence and distribution of teacher-identified special health-care needs across three successive population cohorts.

AIM: Some children's special health-care needs (SHCN) are formalised at the start of schooling (established SHCN), but a larger proportion start with difficulties that are milder or not yet diagnosed (emerging SHCN). This study explores whether: (i) the prevalence of teacher-identified SHCN (both overall and according to type of needs) and (ii) distribution across disadvantaged communities have changed over three successive population cohorts of Australian children. METHODS: We draw on repeated cross-sectional data from the Australian Early Development Census, a teacher-reported checklist completed on full populations of Australian school entrants in 2009, 2012 and 2015. It includes a measure of SHCN, as well as demographic information. RESULTS: The proportion of children with emerging and established needs was mostly stable from 2009 to 2015 (emerging needs: 17.1-18.9%; established needs: 4.4-4.9%). Change over time was observed in the prevalence of some specific types of impairment. Speech impairment rose by 14.7% for children with emerging needs, and emotional problems rose by 13.7% for children with established needs. Children living in the most disadvantaged neighbourhoods had higher odds of SHCN in all years (e.g. emerging needs relative risk ratio 1.65 (99% confidence interval 1.55-1.75) in 2015; established needs relative risk ratio 1.88 (99% confidence interval 1.71-2.06) in 2015). CONCLUSIONS: A large proportion of children starting school each year have SHCN. The types of SHCN that children present with increasingly reflect complex difficulties that require input from both the health and education sectors. Effective responses also need to consider the added impact of disadvantage.

More than a snapshot in time: pathways of disadvantage over childhood.

Background: Disadvantage rarely manifests as a single event, but rather is the enduring context in which a child's development unfolds. We aimed to characterize patterns of stability and change in multiple aspects of disadvantage over the childhood period, in order to inform more precise and nuanced policy development. Methods: Participants were from the Longitudinal Study of Australian Children birth cohort (n = 5107). Four lenses of disadvantage (sociodemographic, geographic environment, health conditions and risk factors), and a composite of these representing average exposure across all lenses, were assessed longitudinally from 0 to 9 years of age. Trajectory models identified groups of children with similar patterns of disadvantage over time for each of these lenses and for composite disadvantage. Concurrent validity of these trajectory groups was examined through associations with academic performance at 10-11 years. Results: We found four distinct trajectories of children's exposure to composite disadvantage, which showed high levels of stability over time. In regard to the individual lenses of disadvantage, three exhibited notable change over time (the sociodemographic lens was the exception). Over a third of children (36.3%) were exposed to the 'most disadvantaged' trajectory in at least one lens. Trajectories of disadvantage were associated with academic performance, providing evidence of concurrent validity. Conclusions: Children's overall level of composite disadvantage was stable over time, whereas geographic environments, health conditions and risk factors changed over time for some children. Measuring disadvantage as uni-dimensional, at a single time point, is likely to understate the true extent and persistence of disadvantage.

The impact of multidimensional disadvantage over childhood on developmental outcomes in Australia.

Background: Understanding the relationship between different aspects of disadvantage over time and domains of child development will facilitate the formulation of more precise policy responses. We examined the association between exposure to aspects of disadvantage over the childhood period (from 0-9 years) and child development at 10-11 years. Methods: We used data from the nationally representative birth cohort of the Longitudinal Study of Australian Children (n = 4979). Generalized linear models with log-Poisson link were used to estimate the association between previously derived disadvantage trajectories (in each of four lenses of sociodemographic, geographic environments, health conditions and risk factors, and a composite of these) and risk of poor child developmental outcomes. Population-attributable fractions were calculated to quantify the potential benefit of providing all children with optimal conditions for each developmental outcome. Results: Trajectories of disadvantage were associated with developmental outcomes: children in the most disadvantaged composite trajectory had seven times higher risk of poor outcomes on two or more developmental domains, compared with those most advantaged. Trajectories of disadvantage in different lenses were varyingly associated with the child development domains of socio-emotional adjustment, physical functioning and learning competencies. Exposure to the most advantaged trajectory across all lenses could reduce poor developmental outcomes by as much as 70%. Conclusions: Exposure to disadvantage over time is associated with adverse child development outcomes. Developmental outcomes varied with the aspects of disadvantage experienced, highlighting potential targets for more precise policy responses. The findings provide evidence to stimulate advocacy and action to reduce child inequities.