Abstract
Objectives
Population-level studies may elucidate the most promising intervention targets to prevent negative outcomes of developmental vulnerability in children. This study aims to bridge the current literature gap on identifying population-level developmental vulnerability risk factors using combined social and biological/health information.
Methods
This study assessed developmental vulnerability among kindergarten children using the 2016 Early Development Instrument (EDI) and identified risk factors of developmental vulnerability using EDI data cross-linked to a population-wide administrative health dataset. A total number of 23,494 children aged 5–6 were included (48% female). Prenatal, neonatal, and early childhood risk factors for developmental vulnerability were investigated, highlighting the most important ones contributing to early development.
Results
The main risk factors for developmental vulnerability were children with a history of mental health diagnosis (risk ratio = 1.46), biological sex–male (risk ratio = 1.51), and poor socioeconomic status (risk ratio = 1.58).
Conclusion
Our study encompasses both social and health information in a populational-level representative sample of Alberta, Canada. The results confirm evidence established in other geographic regions and jurisdictions and demonstrate the association between perinatal risk factors and developmental vulnerability. Based on these results, we argue that the health system should adopt a multilevel prevention and intervention strategy, targeting individual, family, and community together.
Introduction
In the area of determinants of health and disease (DOHaD) there is a growing body of knowledge that can inform policy and action plans to increase the human potential for a healthy life. 1 Early childhood development from birth to 8 years old is multifaceted, including physical, socioemotional, cognitive, and motor development. 2 The prenatal period and the first 5 years of a child's life are especially important due to rapid brain development, which is sensitive to biological and environmental influences. Prenatal and postnatal care, and early detection and treatment of health concerns are important when considering children's developmental health. From both child development and economic perspectives, preventive strategies are most effective when they are proportionately tailored to specific risk factors and timing in the development. 3 In relation to health economics impact, there is an estimated doubling of return on investment to society for every dollar paid toward supporting healthy early childhood development. 3
Understanding the most important risk and protective factors for child development is important to inform decisions and policy development for the deployment of programs and services to support vulnerable children and their families. Vulnerability in children can be broadly defined as the outcome of the interaction between biological and social factors that make children prone to certain risks in their development. 4 In utero exposure to substances, prenatal exposure to maternal diabetes,5–8 and lack of essential nutrients during pregnancy 9 are examples that may negatively impair children's development, whereas breastfeeding during infancy is a well-known protective factor for children's optimal neurodevelopment. 10 However, based on our rapid literature review, among the studies focusing on understanding how early life events may shape children's development (N = 25), only around half of those (N = 12) focus on prenatal and neonatal risk/protective factors, while only a fifth (N = 5) investigated prenatal, neonatal, and early childhood determinants (Supplemental Table S1). Also, the 2019 Canadian Health Survey on Children and Youth reported a need for additional information for those individuals under the age of 12. This calls for more converging evidence for the potential prenatal, neonatal, and early childhood factors related to early childhood development.
Studies across Canada often use the Early Development Instrument (EDI) to assess developmental vulnerability by identifying children whose skills and behaviors are below the levels exhibited by most of their peers.11–13 The EDI is a kindergarten-teacher-completed questionnaire that provides information about children's ability to meet age-appropriate developmental expectations, as shaped by their experiences in the first 5 years of their life. 14
Studies using administrative health data already confirmed common risk factors of developmental vulnerability, yet individual studies are usually limited in scope, for example focusing only on social 15 or biological/health7,13 information, or lack a population-level representative sample.16,17 Linking data from different sources including both biological and social factors may help to reduce this current knowledge gap by generating evidence with enhanced external validity, providing a more comprehensive perspective of social economics and health utilization, which in turn can promote a better involvement of policymakers. 18 In this study, we sought to understand how prenatal, neonatal, and early childhood factors are associated with kindergarten-aged children's vulnerability in the Canadian province of Alberta and to compare these results with other provinces in Canada and other countries, within the broader context of known social and biological determinants of health.
The primary goal of the study is to bridge the knowledge gap in the literature by the development of a cross-linked dataset through linking multiple population-level province-wide health administrative databases to the 2016 collection of EDI data. A secondary goal is to confirm the association between the important prenatal, neonatal, and early childhood factors that contribute to early development specifically in the Alberta population, which have not been explored in the literature, and to enable comparison of the results to other jurisdictions in Canada and other countries. The study results may facilitate a better understanding of developmental vulnerability in Canada and other countries and could inform policymakers and guide vulnerability risk reduction and prevention.
Methods
Study population and variable extraction
The province-wide collection of EDI data for Alberta, sponsored by the Alberta Ministry of Education, was carried out in February and March 2016. This data collection process involved obtaining active consent from parents. During that period, Alberta had a total of 69,486 children aged 5 and 6 years old; 31,128 (44.8%) of them did not participate in the EDI data collection due to being homeschooled, living in remote areas, or due to school opt-outs. An additional 7677 questionnaires did not meet eligibility criteria (e.g. missing data, under 30 days in the classroom, parental consent was missing, incorrect completion of the questionnaire) and were excluded. Then, data from the EDI were linked with the administrative databases from the Ministry of Health, Government of Alberta based on identifiable information (i.e. name, biological sex, and date of birth) and unique provincial health number, resulting in a cohort size of 28,952. Eight databases were linked with EDI data, including Alberta Health Care Insurance Plan Physician Claims, the National Ambulatory Care Reporting System, the Canadian Institute of Health Information–Discharge Abstract Database, the Alberta Health Care Insurance Plan Population Registry Database, Alberta Pharmaceutical Information Network database and Alberta Human Services Drug Supplement Plan database, Alberta Notice of Live Birth or Stillbirth database, Statistics Canada Census Data (2016). For a description of the databases, please see Supplemental material. Only linked records were used in the study.
Finally, we retrieved neonatal and prenatal information from the Alberta Notice of Live Birth or Stillbirth records. Children not born in Alberta do not have records from this database and were excluded from the analysis. The final analytical study sample consisted of 23,494 children (mean age = 5.68 years and SD = 0.33; 48.0% females). The flowchart of the sample exclusions is shown in Figure 1.

Study cohort flow chart.
This study was approved by the Health Research Ethics Board—Health Panel at the University of Alberta (Pro00104650_REN1). Informed consent was waived by the institutional review board due to the secondary analysis nature of the study. Given the anonymization of the data, the researcher's access to it presents minimal risks.
Outcome measures
The EDI's validity, reliability, and consistency have been reported, showing a high degree of consistency across several countries. 19 The questionnaire includes 103 items grouped into five relevant developmental domains: physical health and wellbeing, social competence, emotional maturity, language and cognitive development, and communication and general knowledge. 14 Each child's domain summary scores were derived by averaging scores from domain-specific questions with a range from 0 to 10, where a higher score indicates a higher developmental status. Each domain score was then categorized as “developmentally vulnerable” when the range for a specific domain fell on or below the 10th percentile of the distribution in that domain, which indicates risk for difficulties (for more details, please visit https://edi.offordcentre.com/resources/edi-cohort-reports/). Children who score in the “developmentally vulnerable” range in one or more domains are considered vulnerable overall. This was the study's main outcome measure, as it encompasses all areas of development and is strongly predictive of poor academic and behavior outcomes in later grades, 15 often more so than a domain-specific vulnerability. 20 As most of the research published using EDI data uses the same Canadian baseline threshold (i.e. 10th percentile of the Canadian normative distribution), it is reasonable to compare them among different locations. Analyses using domain-specific outcomes were also conducted and are presented in the supplementary material (Supplemental Tables S6-S10).
Study predictors
To facilitate study interpretation and reduce multicollinearity bias, raw variables with duplicated meanings, or moderately and highly correlated (r > 0.5) were excluded from the study. A total of 28 variables were included as predictors (see Supplemental Tables S2 and S11). They included biological factors, such as sex assigned at birth and child's and mother's chronic and mental conditions, and socioenvironment factors, such as history of health services utilization, mother's drug and multivitamin use, socioeconomic status (SES) as measured by whether the child was part of a subsidy group, and community sociodemographic characteristics. For a complete list of variables included in the regression model and details on the predictor variables please refer to the Supplemental materials.
Statistical analysis
Alberta-born cohort characteristics were compared between the vulnerable and nonvulnerable children across several selected variables with Chi-square tests (Table 1). See Supplemental Table S4 for comparison of all variables. Likewise, we compared children for whom EDI data were available (n = 28,952) with those without EDI data (n = 40,534) to investigate whether these groups had similar demographic characteristics and patterns of health service utilization (see Supplemental Table S3).
Characteristics of the study cohort by vulnerability in one or more domains.
Note: # χ2 Test was used for categorical variables. T-test was used for continuous variables.
Multivariate logistic models were used to identify risk factors associated with vulnerability in children using SAS, version 9.4. Statistical tests with p-values lower than 0.05 were considered statistically significant. This analysis was performed for Alberta-born children with vulnerability in one or more domains and with vulnerability in each of the five domains as outcomes. Numeric variables with highly skewed distributions were converted to binary equivalents (1 = high risk, 0 = low risk) to ease the interpretation of results. The cut-offs for these dichotomous variables were chosen at the 90th percentile to code the high-risk groups as 1, and the cut-offs were sometimes rounded to facilitate interpretation (for more details, see Supplemental Table S2).
Odds ratios from logistic regression models tend to overestimate the relative risks when the outcome is common (e.g. > 10%). 21 For more accurate relative risk interpretation, risk ratios were computed 22 to assess the effects risk factors had on the vulnerability risk in conjunction with adjusted p-values (using false discovery rate 0.05). Dichotomous variable categories were selected such that the reference group did not undergo any intervention (e.g. breastfeeding = “No,” preterm pregnancy = “No”). Due to the high number of variables included in the regression model, only those variables that reached statistical significance were reported in the results. All variables are reported in Supplemental materials (see Supplemental Table S5).
Among all data sources, biological data collected via the administrative health data Alberta Notice of Live Birth or Stillbirth form at the child's birth in a hospital had the highest proportions of missing data. To explore the risk factor potential of those data, missing values were replaced via imputation methods either based on medians (for continuous variables) or modes (for categorical variables), when <30% of the original variable was missing. Logistic models were applied to the data after imputation.
Results
Descriptive statistics
Our analyses found statistically significant differences between the group of children with EDI data (whole EDI cohort) and the group of children without EDI data (non-EDI) in SES/subsidy and mental health utilization in physician claims (Supplemental Table S3). Children that did not participate in the EDI assessment have a higher rate of subsidy (12.43%) than children that did take part in the survey (8.33%). We found a slightly higher proportion of children without EDI data had mental health utilization in physician claims (88.9%, compared to 88.2% of children with EDI data). No statistically significant between-group differences were found in demographic characteristics and patterns of health service utilization.
A total of 6702 children (28.5%) were developmentally vulnerable. Relative to nonvulnerable children (n = 16,792), a higher proportion of the vulnerable children were males (21% of girls were vulnerable compared to 35% of boys), belonged to a subsidy group (54% of those who received subsidy were vulnerable), and were part of a drug benefit plan for at least 1 year (51% of children that were part of the plan were vulnerable). The results for all variables can be seen in Table 1 and Supplemental Table S4. Definitions of all variables are in Supplemental Table S2.
Vulnerable versus nonvulnerable children
The results of the logistic regression examining the contribution of potential risk factors to vulnerability are presented in Table 2 (see Supplemental Table S5 for the results for all variables). Overall, children who experienced socioeconomic adversity had 1.58 times the risk of being vulnerable than nonsubsidy children. Similarly, after adjusting for other risk factors, the risk for vulnerability among males relative to females is 1.51 times higher, 1.30 times higher for prenatal exposure to nicotine, and 1.46 times higher for every additional year of mental health diagnosis.
Logistic regression model results for children with 1-or-more vulnerabilities at ages 5 and 6 (n = 23,494).
Note. *Adjusted p-value based on false discovery rate correction at 0.05. All p-values presented in this table are significant at p < 0.05, see Supplemental Table S5 for the full table.
Breastfeeding at birth was associated with a 13% less risk of vulnerability compared to children who were not breastfed. Further, a 4% reduction of risk was observed for every additional year the child had asthma. Finally, a 1% increase in the proportion of individuals in the community with higher education reduced the risk of vulnerability by 1%.
Follow-up analyses explored the association of these risk factors on vulnerability in each EDI domain (Supplemental Tables S6–S10). Increased risk of vulnerability in each domain was associated with the child's socioeconomic/subsidy group, years of mental health diagnosis, and prenatal exposure to smoking and other addictive substances. There were no substantial differences in terms of the identified risk factors between Alberta-born children and all children cohorts.
Discussion
In this comprehensive, population-level linked dataset including perinatal and birth data as well as child development at school entry in the Canadian province of Alberta, we confirmed the universality of key risk factors associated with the highest risk of vulnerability: SES, biological sex, and children's mental health. Studies including such a broad range of perinatal, neonatal, and early childhood variables, both biological and social, as predictors of child development outcomes are rare, and so far, come only from a few in Canada13,23–30 and Australia. 31 By conducting our study in the Canadian province of Alberta, we both confirm the previous findings and add a unique contribution of extended universality to this body of knowledge. These results call for further research and practical guidelines in diminishing the negative impact of mental diseases and poor SES on child development and focusing on sex-specific developmental vulnerability.
Biological sex at birth might be indicative of vulnerability as our analysis shows that boys have a 50% greater risk of being developmentally vulnerable than girls. Similar results were found in other studies in Canada26,27,32 and Australia.30,32–34 Dea et al. 32 reported almost twice the risk for developmental vulnerability in boys when compared to girls by using the EDI data in Quebec, Canada. Using different data sources, Cabaj et al. 26 and Mughal et al. 27 reported that boys have a higher risk of problem behaviors at age 8 and are more prone to develop communication and personal-social delays at age 3, respectively. In Australia, previous reports showed that male children are at higher risk of developmental vulnerability, motor gross delay, and executive function difficulties at age 5. 30
Several components of SES were associated with vulnerability, as previously reported by studies using the EDI data in Canada24,32,35 and the Australian version data (Australian Early Development Census, AEDC).32,34,36 Our results suggest that living in an area with a higher proportion of people with higher education was a protective factor for child vulnerability. This finding is consistent with the known compounding effect of low SES and education,30,34 where children from low SES families are more likely to demonstrate poor outcomes, with limited exposure to a stimulating environment and the lack of family resources to stimulate education suggested as a possible mechanism35,37 which can later affect their school attendance and transfer to high school. 38 Relatedly, we identified a higher proportion of individuals who do not speak English/French in the child's neighborhood. This higher proportion may contribute to poor outcomes in education and is associated with higher vulnerability risks.
The present study showed an association between a child's poor mental health and school readiness difficulties (i.e. children's ability to successfully engage in the task demands of school). By analyzing the AEDC data, Green et al. 39 showed that childhood developmental vulnerability indicators at age 5 are a major contributor to children's mental illness at age 13. Together, these findings add insights to the current knowledge of the association between mental health issues at early ages and increased psychiatric diagnosis and symptom severity later in life. 40 Interestingly, maternal and paternal mental illness is also associated with developmental vulnerability of children. Saunders et al., 24 Wall-Wieler et al., 13 and Bell et al., 41 all of them using the EDI data or the Australian version data (AEDC) showed that exposure to parents with a psychiatric diagnosis increases the risk of developmental vulnerability, difficulties in social competence, physical health and wellbeing, and emotional maturity. In addition to the psychiatric diagnosis of parents, the mental health history in children also had a similar impact on vulnerability. Mental illness is one of the global leading causes of years lived with disability (YLDs; i.e. years of life lost due to time lived in states of less than full health), accounting for almost 15% of global YLDs. 42 The burden due to mental disorders is seen across all age groups and emerges even before five years of age. 42 This highlights the need for early identification and intervention to support children in their mental health, particularly as young individuals with psychiatric disorders often face challenges in obtaining an accurate diagnoses. 43
We also identified other risk factors for children's vulnerability, confirming previous studies in the field. For example, exposure to tobacco, opioids, and other substances during pregnancy are contributors to poor developmental outcomes in children.6–8,34,44 In addition, in utero exposure to these substances can result in preterm birth,6,8 further contributing negatively to early childhood development as shown by previous studies. 24 On the other hand, breastfeeding and multivitamin and folic acid intake showed a significant trend (p = 0.050, see Supplemental Table S5) and are associated with lower risks for childhood development. Those are important factors of neurodevelopment since many important brain formation events are dependent on folic acid and vitamins, such as proliferation and growth of glial and neuronal cells and the synthesis of neurotransmitters. 45 Also, breastfeeding is beneficial for all infants as it has important nutrients that influence the development of cognitive and motor abilities, and socioemotional competencies in children. 10
Despite many strengths, our study also has limitations. The EDI data privacy impact assessment did not allow us to link EDI scores with parent or family information. Due to this limitation, we did not have access to the original family environment or the parents’ health status (chronic disease conditions and mental health issues), which are known to impact children's early development and their vulnerabilities.11–13 Also, our final cohort covered approximately 30% of Alberta children due to the mandatory informed consent process and the options for school boards to opt out of the program, and EDI data were not collected for First Nation Band-operated schools. Thus, results need to be interpreted with caution due to a potential sample selection bias. The representativeness of the study sample is further impacted by reducing the cohort to Alberta-born children with valid EDI data. A sizable proportion of the sample (n = 5458) had missing Alberta Notice of Live Birth or Stillbirth form data, which may be due to the busy schedule of health providers in hospitals and the low priority for nurses to record answers thoroughly on the form, enforcing the use of imputation methods that could potentially underestimate variability due to repetition of the same value within variables. In addition, since we found a significant difference in the proportion of people receiving subsidies (Supplemental Table S3), in conjunction with imputing systematically missing data, it is likely there are group differences in other unmeasured factors between the study cohort and the larger EDI cohort. All considered, the study sample selection may have underestimated the proportion of vulnerable children. In addition, the study was designed to explore risk factors associated with vulnerability, not to establish causality. Thus, even though the dataset collected may imply causality, due to the temporal separation between variables and outcome, the modeling results should be interpreted with caution.46–48
Conclusion
The current findings from the analysis of a large cohort of Albertan children are a significant contribution to our body of knowledge concerning the vulnerability of Canadian children in the context of DOHaD. By linking data on child development at school entry with a variety of health administrative data including data collected from birth and by using a population-level sample from Alberta, we included both social and health information in a representative sample of Alberta, Canada. Our results are in line with existing findings that the mother's substance use, the child's chronic and mental disease status, male biological sex, and socioeconomic status are the main risk factors of developmental vulnerability, while breastfeeding and multivitamin with folic acid supplementation are associated with lower risk of developmental vulnerability. Our results confirm evidence established in other geographic regions and jurisdictions and demonstrate the association of perinatal risk factors for Alberta children. Although it is extremely important to know risk factors for policymakers and for prevention, our top risk factors may be challenging to address. It would take time to change at a population level, making it difficult to make informed decisions for developing programs and services aimed to support specifically vulnerable children and their families. The current health system is designed to treat diseases and to invest in procedural interventions instead of focusing on preventive care. Our results are in favor of long-term multilevel intervention, in which individuals, families, and communities are targeted together.
Supplemental Material
sj-docx-1-dhj-10.1177_20552076231210705 - Supplemental material for Risk factors for developmental vulnerability: Insight from population-level surveillance using the Early Development Instrument
Supplemental material, sj-docx-1-dhj-10.1177_20552076231210705 for Risk factors for developmental vulnerability: Insight from population-level surveillance using the Early Development Instrument by Fernanda Talarico, Yang S Liu, Dan Metes, Mengzhe Wang, Dori Wearmouth, Lawrence Kiyang, Yifeng Wei, Ashley Gaskin, Andrew Greenshaw, Magdalena Janus and Bo Cao in DIGITAL HEALTH
Footnotes
Contributorship
BC, AG, and MJ designed the study. DM and MW designed the analytical strategy and helped to interpret the findings. FT conducted the literature review and helped to write the first draft with YSL. All authors contributed to editing the first draft of the manuscript.
Disclaimer
This study is based in part on data provided by Alberta Health. The interpretation and conclusions contained herein are those of the researchers and do not necessarily represent the views of the Government of Alberta. Neither the Government nor Alberta Health express any opinion in relation to this study.
Declaration of conflicting interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Canada Research Chairs, University of Alberta Hospital Foundation, Alberta Synergies in Alzheimer's and Related Disorders, MITACS, Simon & Martina Sochatsky Fund for Mental Health, NARSAD, Alberta Innovates, Young Investigator Grant of The Brain, Mental Health Foundation, Behavior Research Foundation.
Guarantor
BC
Supplemental material
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References
Supplementary Material
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