The Research on Income and Test Scores

A recurring question about school rankings is how much of a school's measured performance reflects the school itself, and how much reflects the circumstances of the students who attend it. This page summarises what published research has found on that question, and explains how this site handles it.

What the research literature reports

The relationship between socioeconomic status (SES) and academic achievement is one of the more heavily studied questions in education research. The most widely cited synthesis is a meta-analysis by Selcuk R. Sirin, published in the Review of Educational Research in 2005.[1] It reviewed studies published between 1990 and 2000, drawing on 74 independent samples covering 101,157 students, 6,871 schools and 128 school districts.[2]

Sirin reported a medium-to-strong relationship between socioeconomic status and achievement.[1] The review also found that the strength of the relationship varies considerably depending on how SES is measured, the unit of analysis (student versus school), the school level, and school location — meaning a single headline correlation understates how conditional the finding is.[1]

A more recent meta-analytic review covering primary and secondary education, published in Educational Psychology Review in 2022, revisits the same question with newer studies.[5]

The Canadian policy analysis

In Ontario specifically, the C.D. Howe Institute publishes Signposts of Success, a series analysing Ontario elementary school test results.[3]Its stated approach is to adjust for students' socioeconomic backgrounds in order to separate what the Institute describes as the parent contribution from the school contribution to measured results.[3]

Two findings from that work are worth noting because they cut in different directions:

• Socioeconomic background is reported to matter, but not to fully determine outcomes — the analysis identifies many schools that perform above what their intake would predict.[3]
• Socioeconomic factors are reported to explain more of the variation in mathematics outcomes than in literacy outcomes, and the predictors differ between Grade 3 and Grade 6.[3]

The first of those findings is the reason this site reports improvement over time as a separate indicator: a school's trajectory carries information that its absolute results do not.

How this site handles the issue

Our approach is to display context and exclude it from scoring. Specifically:

• Every school page shows the median household income of the school's postal area from the Statistics Canada 2021 Census, including the median income figures reported separately for men and women.
• Every school page shows Ministry-published school-level indicators including the share of school-aged children in low-income households and the share of students whose parents have no degree, diploma or certificate.[6]
• Every school page shows the share of English language learners and students receiving special education support.
• None of these figures affect a school's score. No school is scored higher or lower because of the demographic composition of its students.

Reading a score in light of this

The research does not support treating a test-score ranking as a direct measure of teaching quality, nor does it support dismissing results entirely. Two practical implications follow from the published findings:

• Comparisons between schools with similar intakes are more informative about the schools than comparisons across very different catchments. Our city pages group nearby schools for this reason.
• Change over time is less confounded by intake than a single year's absolute result, which is why the Opportunity-Adjusted weighting on our rankings page places the greatest weight on improvement.