A health disorder – either mental, such as autism or anxiety, or physical, such as asthma – early in life can have a big impact on the developmental trajectory of a child. Among otherwise healthy children, close to one in five kindergartners lack the developmental skills needed to take full advantage of school. Among children who have identified special health needs at that age, this proportion rises to almost 80%.
There is growing evidence that socio-economic factors impact children’s health. For example, families of children with disabilities are more likely to experience socio-economic disadvantage and lower income is associated with greater odds of having a limiting health condition by age 10-11. While much is known about how disadvantage impacts the development of children without health disorders, it is unclear if children with health disorders are impacted similarly.
In fact, there is reason to believe socio-economic disadvantage may impact children with health disorders even more than typically developing children. Existing evidence shows that low socioeconomic status affects neurocognitive development and the speed of brain development.
In addition, socio-economic disadvantage could affect types of disorders differently, as well as across regions. For example, the quality of early identification may differ across provinces or communities.
Learning how the patterns of this impact differ across regions is crucial for designing early interventions, deciding on the type and location of services, and understanding how to ensure children with health disorders are given the best possible chance to succeed.
Until recently, the question of how developmental outcomes for young children with special health needs are influenced by risk factors could not be addressed at a population level. But thanks to ground-breaking work at the Offord Centre for Child Studies we can begin to learn more about this influence.
The Canadian Children’s Health in Context Study (CCHICS) uses a population-based database of developmental outcomes in kindergarten (as measured by the EDI), which includes information on diagnosed health disorders in early childhood merged with Census and Taxfiler data using children’s postal codes. This dataset makes it possible to investigate the impact of health disorder and socioeconomic disadvantage on children’s developmental outcomes at school entry.
Initial analysis of EDI data for 990,502 children from 2004 to 2015 showed the prevalence of childhood health disorders in Canadian neighbourhoods, excluding those with fewer than 10 children, ranged from 1.9% to 49.3%, with an average of 16.8%. We also learned that neighbourhood-level SES was significantly related to the prevalence of health disorders in a neighbourhood. For each one standard deviation decrease in SES, the prevalence of health disorders rose by 2.4%.
The reported disorders included an identification of special needs, having a functional impairment limiting the child’s ability to participate in classroom activities, or diagnosed conditions (i.e. physical or mental health disorder).
Another benefit of this unique dataset is the ability to learn about specific health conditions in more detail. For example, compared to children that exhibited few to none of these behaviours, highly anxious children were significantly more likely to be male, have English/French as a second language, and have a special needs designation. Although the prevalence remained fairly consistent over time across Canada (2.1% to 3% per year), it varied across provinces and territories, from 1.2% (Prince Edward Island) to 5.0% (Northwest Territories). Highly anxious children were also between 3.4 and 6.2 times more likely to be vulnerable in the physical, social, cognitive, and communication domains of development, compared to their less anxious peers.
For a full description of how the research team plans to conduct the CCHICS study please read our protocol paper.
About EDI on the Go This article was originally featured in EDI on the Go, the EDI newsletter. Each issue highlights a community implementation or research project using the EDI. The newsletter also features the latest EDI news and events. Become a subscriber today.