What is the Middle Years Development Instrument (MDI)?

What you need to know

Positive experiences in middle childhood build the foundation for healthy adolescence and adulthood. Data from the MDI guide schools, families, and communities to improve the lives of children during these critical years of growth and transition.

Children's Voices

The Middle Years Development Instrument is a voluntary self-report questionnaire completed online by children in Grades 4 through 8 about their lives in school, in the home and in the community, from their own perspective.

Full Picture
The data collected on the MDI provide educators, community members, policy makers, and families with reliable and valid information about the well-being, health, and assets of children during this critical time in their development.
Used Across the World

The MDI has been implemented in British Columbia, across provinces and territories in Canada, and by international governments and research institutions  with language translations and cultural adaptations made where appropriate.

Measures a time of change

Experiences in the middle years—especially between the ages of 10 to 13 years—have critical and long-lasting effects. During this time, children experience significant cognitive, biological, social, and emotional changes that establish their lifelong identity and set the stage for successful development in adolescence and adulthood.

Strengths-based, Asset Based
The MDI uses a strengths-based approach by asking children questions about the protective factors and assets in their lives that are known to support resilience and optimize their well-being, health, and success inside and outside of school. The assets that are measured on the MDI – such as supportive relationships with adults and peers, and out-of-school time – were selected, in part, because research in the field of resiliency indicates that these assets are both malleable and actionable—that is, people in schools and communities can strengthen and build these assets in the children they serve Schonert-Reichl et al., 2013; Thomson et al., 2017.
Provides a full picture of children's well-being
The MDI is designed to gather data that provide a comprehensive portrait of children’s well-being on five key dimensions shown to be associated with children’s positive development: Social and Emotional Development, Physical Health and Well-Being, Connectedness, Use of Out-of-School Time, and School Experiences. You can learn more about these five dimensions here.
From the voices of the children

Children’s voices matter. One of the core beliefs that is foundational to the MDI is that children’s voices deserve to be heard and responded to by the people across the multiple contexts in which they live. Asking children about their feelings, relationships, environments, and daily lives affords them with a critical opportunity to provide information about their well-being and the assets in their lives that would otherwise be inaccessible. Learning from children directly— in their own voices—can provide essential data to support evidence-based decision making for the design and implementation of programs and practices that promote children’s social and emotional health and well-being, funding priorities, and policy development across sectors.

The MDI is NOT an assessment tool
The MDI is not an assessment of individual children, it is a unique and comprehensive tool that collects and aggregates information on groups of children at a population-level, such as children in a school, a school system, a neighbourhood, or community. The population-level data the MDI collects helps us all – educators, community members, policy makers, families, and researchers – better understand the factors that promote well-being in middle childhood and provides the information needed for taking action to support the well-being of children at a universal level. Indeed, the valuable data provided by the MDI can help provide a deeper understanding of children’s health and well-being during middle childhood and can inform local and provincial efforts to help children thrive in schools and communities. MDI data also support ongoing national and international research aimed at examining the factors that support the social and emotional health, and well-being of children during the middle years.
MDI data is easy to share
Although the MDI is a comprehensive measure that gathers data on child well-being and assets, the ultimate goal of the MDI project is not just about the data—it is about providing important information that can be used to support children to thrive and flourish during these critical years of growth and transition. MDI data are presented in reports for participating schools and communities with easy to understand visualizations and infographics. These reports are designed to help schools and communities understand the current state of children in the middle years and see patterns and variations in their MDI data. MDI reports can be used to gather partners and explore ways to support children’s assets and well-being with parents and caregivers, educators, and leaders in the community. Let the data be your starting point – and use your data to spark discussions, dialogue, and catalyze action to support children’s well-being in the middle years.

Providing the Full Picture

The Middle Years Development Instrument helps shine light on the well-being, health, and assets of children during this critical time in their development. Find out more about what the MDI measures.

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