Early Development Instrument (EDI)

The Early Development Instrument (EDI) is a questionnaire completed by kindergarten teachers for students in their second year of Kindergarten. It was developed by Dr. Dan Offord and Dr. Magdalena Janus at the Offord Centre for Child Studies at McMaster University in Hamilton, Ontario, with the help of experts on child development, kindergarten teachers and school administrators. Originally created as a “whole child” measure of school readiness beyond just academic skills, the EDI gathers information about five core areas of early childhood development: 

• Physical Health & Well-being

• Social Competence

• Emotional Maturity

• Language & Cognitive Development

• Communication Skills & General Knowledge

• EDI data has been instrumental in drawing attention to the connection between children’s development and the social determinants of health and highlighting why the early years matter as a time for focused investment and support.  The Ontario Public Health website states that the social determinants of health are the interconnected non-medical factors that affect our well-being. They include the conditions in which we are born, grow, work, live and age, such as income, education and housing. They also include the broader economic, political and social context. 

• EDI data is collected every three years for all Senior Kindergarten students and aggregated by school board, census division, and public health unit. 

• The Ministry of Education uses the data to identify geographic areas with higher vulnerability rates (children scoring below the 10th percentile in one or more developmental domains). These vulnerability maps help target funding and supports for early years programs, childcare, and community-based interventions.

• EDI results inform early learning strategies, such as Ontario’s Early Years Policy Framework and Full-Day Kindergarten implementation.

• Trends in EDI domains (physical health, social competence, emotional maturity, language/cognitive development, communication skills) guide curriculum adjustments and professional development priorities for educators.

Vulnerability data is used to prioritize investments in: 

• EarlyON Child and Family Centres
• Special education supports
• Community partnerships for mental health and nutrition programs
• Areas with persistent vulnerabilities may receive additional funding for targeted initiatives like speech-language services or family engagement programs.

The EDI tool is not used to diagnose children and does not measure a school or teacher. The information from the EDI helps us to; 

1. learn more about neighbourhoods and groups of children’s strengths and weaknesses
2. look at patterns over time, and
3. see how children will do in elementary school.

• The results of the EDI, in combination with other local data, are meant to help inform communities about the development of their young children so that they may provide the supports necessary for healthy child development.

• For additional information about the EDI in Durham Region, please visit Data in the Early Years.