Authors: Peter Tymms, Adetayo Kasim

EEF Research Paper Series, No. 002, February 2018

EEF response: In line with its goal of narrowing the attainment gap in England, the EEF is considering methods to monitor the differential effects that interventions might have on pupils of varying levels of ability. A change in the dispersion of outcomes of the intervention group would be indicative of differential effects. Based on the results of this study, the EEF updated its Analysis Guidance to request evaluators to report the standard deviations by trial arm before and after the intervention.