EDI in Ontario 2004-2018

The Early Development Instrument (EDI) measures children’s ability to meet age-appropriate developmental expectations at school entry. It focuses on the overall outcomes for children as a health-relevant, measureable concept that has long-term consequences for individuals and populations. The data from its collection helps monitor the developmental health of our young learners.

The EDI has a long history in the province of Ontario. Between 2003/2004 and 2011/2012 the Ministry of Children and Youth Services (MCYS) sponsored three full provincial collections of the EDI, completed over three-year cycles. Most publicly funded school boards participated in each full provincial collection. Some school boards completed their EDI collection across all three years of a cycle, whereas others completed the entire school board in a single year.

The first province-wide implementation of the EDI was completed between 2004-2006. These data constitute the Ontario Baseline or Cycle 1, and are used to determine the 10th percentile cut-offs for subsequent reporting for all cycles.

The Ministry of Education sponsored the EDI collections in 2014/2015 and 2017/2018. In contrast to previous cycles, the fourth and fifth full provincial collections took place entirely in a single year.

Find the full Ontario Cycles 1-5 web report here.

Why look at EDI data over time?

The information collected through the EDI helps us to understand the state of children’s developmental health by connecting the conditions of early childhood experiences to learning outcomes and future successes.

Examining how children are doing over time is important for mobilizing stakeholders towards change. Focusing on strengthening the areas in which children are vulnerable allows schools, communities, and governments to make decisions on how to best support early development. Investigating how children’s developmental health is changing over time can also allow for evaluation and strategic planning around what is currently being done to support children and their families.

This report provides trends across all five provincial collections of the EDI in Ontario. A one-page summary of the changes between Cycles 4 and 5 is available online. The full report can also be downloaded as a PDF.

Long-Term Trends
  • Vulnerability is trending lower in two domains
    • Language & Cognitive Development (7.5% in Cycle 5 vs. 9.6% in Cycle 1)
    • Communication Skills & General Knowledge (10.0% in Cycle 5 vs. 12.1% in Cycle 1)
  • Vulnerability is trending higher in three domains
    • Physical Health and Well-Being (16.3% in Cycle 5 vs. 12.9% in Cycle 1)
    • Social Competence (9.9% in Cycle 5 vs. 9.3% in Cycle 1)
    • Emotional Maturity (11.3% in Cycle 5 vs. 10.3% in Cycle 1)

Change since 2015
  • Trend continuation
    • Vulnerability in Physical Health & Well-Being continues to rise (16.3% in Cycle 5 vs. 16.1% in Cycle 4)
    • Vulnerability in Communication Skills & General Knowledge continues to fall (10.0% in Cycle 5 vs. 10.2% in Cycle 4)
  • Trend reversal
    • Vulnerability in Language & Cognitive Development rose from Cycle 4 (6.7%) to Cycle 5 (7.5%)
    • Vulnerability in Social Competence dropped from Cycle 4 (10.7%) to Cycle 5 (9.9%)
    • Vulnerability in Emotional Maturity dropped from Cycle 4 (12.3%) to Cycle 5 (11.3%)

Number of Children in Analysis

Note: Numbers may not exactly match previously released reports as the EDI now requires children to have been in class for more than one month to be included in any analyses. This change was made as part of improving EDI methodology and creating consistency across provinces.

Children without Special Needs

*Children are excluded if they are not in senior kindergarten, have been identified as having special needs as reported by the teacher, have not been in class for more than one month, or do not have a minimum number of items completed on the EDI questionnaire.

Children with Special Needs

Under the definition of special needs is a broad range of disorders affecting behaviour, communication, as well as physical or intellectual development. Children with special needs often contend with multiple problems, which require tailor-made, flexible support. These children may also have above average abilities in certain areas, adding to the complexity of providing appropriate support to help them reach their optimal development.

*Children with Special Needs meeting all other inclusion criteria (are in senior kindergarten, have been in class for more than one month, and have a minimum number of items completed on the EDI questionnaire) are reported on separately from children without Special Needs.

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It is important to understand the demographic information of the population as these factors may influence EDI scores.


The following information includes children that are in senior kindergarten, have not been identified by teachers as having special needs, have been in class for more than one month, and have a minimum number of items completed on the EDI questionnaire.

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Domain Scores

The EDI measures children’s ability to meet age-appropriate developmental expectations in five general domains.


Icons_EDI Phys

Physical Health and Well-Being

assesses children’s physical readiness for the school day, physical independence, and gross and fine motor skills.

Icons_EDI Soc

Social Competence

assesses children’s willingness to explore new things, their approaches to learning, the amount of respect and responsibility they show, and their overall social competence.

Icons_EDI Emo

Emotional Maturity

assesses children’s prosocial and helping behaviour, their aggressive behaviour, their ability to balance between too fearful and too impulsive, and their amount of hyperactivity and inattention.

Icons_EDI LanCog

Language & Cognitive Development

assesses children’s basic and advanced literacy skills, basic numeracy skills, interest in math and reading, and memory.

Icons_EDI Comm

Communication Skills & General Knowledge

assesses children’s ability to communicate in socially appropriate ways, use language and story-telling, and age-appropriate knowledge of life and the world around them.

Please visit the Domains and Subdomains section of our website to learn more about the aspects of development included in each domain.

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A cut-off is a point of the Ontario Baseline distribution of scores. It is used to characterize children as either vulnerable, at risk, or on track. The 10th percentile cut-off is the score below which children are considered vulnerable. The 25th percentile cut-off is the score below which children are considered to be at risk. The 25th percentile cut-off is the score above which children are considered to be on track.


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Distribution of EDI Scores

Please note: Distributions may not equal 100% due to missing values in a domain.

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Vulnerable describes the children who score below the 10th percentile cut-off of the Ontario Baseline population. Vulnerability data indicates a percentage of children who are struggling in comparison to the Ontario Baseline data.


Research linking EDI findings to later educational data demonstrate that, on average, kindergarten vulnerability predicts ongoing vulnerability in the school system. Numerous studies have shown that early vulnerability predicts a child’s lifelong health, learning, and behaviour.

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Exploring subdomains can help determine the areas of development influencing vulnerabilities and strengths in each domain. For example, subdomains in which a large percentage of children are doing poorly can be used to inform the action needed to address children’s weaknesses.

Some subdomains represent skills that a child in kindergarten is expected to have mastered already (e.g., physical independence). Other subdomains represent areas of development that are still emerging (e.g., prosocial behaviour).

Please visit the Domains and Subdomains section of our website to learn more about the aspects of development included in each subdomain.

Please note: Subdomain groups may not equal 100% due to missing values.
Physical Health and Well-Being

Social Competence

Emotional Maturity

Language & Cognitive Development

Communication Skills & General Knowledge

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Multiple Challenge Index

A child with scores below expectations on nine or more of the 16 subdomains is considered to have multiple challenges.


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Additional resources


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