Background and purpose: Studies of education and learning that were described as experiments have been carried out in the USA by educational psychologists since about 1900. In this paper, we discuss the history of randomised trials in education in the USA in terms of five historical periods. In each period, the use of randomised trials was…

Background: Current policy discourses emphasise the importance of evidence in education, including evidencing the impact of teacher professional learning on student outcomes. Randomised controlled trial (RCT) designs are promoted to measure 'impact'. Recent debates about this reflect longer standing methodological disputes. Advocates of…

Background: The use of randomised controlled trials (RCTs) in education has increased significantly over the last 15 years. However, their use has also been subject to sustained and rather trenchant criticism from significant sections of the education research community. Key criticisms have included the claims that: it is not possible to undertake…

Background: The Education Endowment Foundation (EEF) is an independent charity that was established in 2011 with the explicit aim of breaking the link between family income and educational achievement in England. Over the seven years since its inception, EEF has contributed to the existing evidence base by funding over one hundred randomised…

Background: The Scandinavian countries have a long history of implementing social interventions, but the interventions have not been examined using randomised controlled trials until relatively recently compared with countries like the United States and the United Kingdom. Purpose: The purpose of this paper is to examine the history of randomised…

Background: Educational interventions are often complex, and their outcomes could be due to factors not focused on in the impact evaluation. Therefore, educational evaluations using a randomised control trial (RCT) design approach need to go beyond obtaining the impact results alone. Purpose: Process evaluation is embedded in the evaluation design…