Randomised controlled trials are considered the gold standard for evaluating interventions – but how and when should they be used, and what do teachers need to know about them?
A randomised controlled trial (RCT) is a study that determines the effectiveness of an intervention by comparing the effects on those in a group receiving the intervention and those in a control group, who will receive either a placebo or the standard practice (not the intervention being studied).
Participants are randomly assigned to each group, and both groups are then followed up to see if there are any differences in the outcomes between them.
RCTs are often considered to be the gold standard for evaluating the effectiveness of interventions because they help to ensure that results are not due to chance.
By randomly assigning participants to the groups, researchers can be confident that the cohorts are similar at the start of the study, which means that any differences in the outcomes between them are more likely to be due to the intervention being studied.
How does it work in the classroom?
Reflecting in Tes in 2019 on 100 years of education RCTs, researchers Ben Styles and Carole Torgerson explained that more than half of schools in England had taken part in RCTs to evaluate the impact of educational interventions on pupil outcomes.
They explained that, despite “unwavering support from the teaching profession”, there were still misconceptions and a considerable amount of confusion surrounding such trials and the ways that they operate.
They said: “Something we used to hear a lot of in the early trials we ran was disappointment from schools assigned to the ‘control’ condition - the group that does not receive the intervention being assessed by the research.
“It was quite common for these teachers to override the random nature of the trial and deliver the intervention to those pupils whom they felt might benefit most.”
The pair explained that their response in such situations is to reassure these disappointed schools that no one knows at that point if the intervention works, and so to deliver it to a student who isn’t meant to receive it is to disrupt the trial and make it less likely that a genuine effect can be detected.
They said: “It’s a ‘greater good’ argument, which relies on an understanding of the bigger picture.”
The Education Endowment Foundation (EEF) is an independent charity dedicated to breaking the link between family income and educational achievement.
To achieve this, it summarises the best available evidence for teachers; its Teaching and Learning Toolkit, for example, is used by 70 per cent of secondary schools.
The charity also generates new evidence of “what works” to improve teaching and learning, by funding independent evaluations of high-potential projects, and supports teachers and senior leaders to use the evidence to achieve the maximum possible benefit for young people.
