Value-added measures used for league tables may unfairly penalise some schools by ignoring the impact of pupils’ genetics.

The claim has come from researchers at the University of Bristol in a report titled Testing the Validity of Value-Added Measures of Educational Progress with Genetic Data.

Bristol’s MRC integrative epidemiology unit senior research associate Tim Morris said: “These findings suggest that value-added progress measures should be used with caution as they may misattribute pre-existing differences in children’s ability to schools and teachers.”

Mr Morris said league tables might, therefore, “over or understate the effectiveness of schools depending on their intake, and teachers may be unjustly penalised based on their luck of the draw regarding the class they are given.”

He added: “Incorporating genetic information could profoundly affect our understanding of education and offer new ways to investigate the effectiveness of educational policy.”

Researchers used data from 6,518 participants of the Children of the 90s Longitudinal Study, and the UK National Pupil Database of examination results.

They wanted to know whether value-added progress measures reflected only school and teacher performance, or were influenced by genetic differences among students, since the latter do not change over time.

They found genetic differences could affect some value-added measures built from teachers’ assessments of students’ ability.

This meant the value-added measures were only partly based on schools’ and teachers’ contributions to pupils’ education and were also dependent on the genetic nature of the intake concerned.

Resulting school league tables were therefore biased and might unfairly penalise some schools.

A Bristol briefing paper for educationalists on this research can be seen here.