Randomised Controlled Trials

Two groups of game pieces with one in the middle

Randomised controlled trials (RCTs) help identify whether a change in policy, intervention or practice results in changes in outcomes. RCTs randomly assign people into two groups: 'treatment' and 'control'. The intervention or change is applied to the treatment group but not the control group and the outcomes of both groups are observed.

Being able to isolate and test different policy decisions produces the best evidence for decision makers. Well-executed RCTs minimise the possibility that observed changes in outcomes are a result of different changes to the one tested. Often, policy changes are implemented without knowledge of their impact; RCTs allow us to understand 'what would have happened otherwise'.

RAND Europe uses RCTs for simple and complex social interventions in several areas of policy, including education, employment and criminal justice. We have expertise in planning and undertaking all elements of both randomised trials and the process evaluations that enable us to answer the 'why' and 'how' questions about results.

Featured Research

  • Little girl blows and brings out letters of words

    Early language intervention shows promise

    A randomised controlled trial into the effectiveness of the Nuffield Early Language Intervention found that it appeared to have a positive impact on children’s language skills and that training and support for staff also had a positive effect on children.

Selected Research

  • School students discussing science with their teacher in class

    RCT evaluates the Maximising the Impact of Teaching Assistants programme

    In the first randomised controlled trial studying the efficacy of a whole-school intervention aimed at improving how schools deploy TAs in everyday classrooms, researchers found MITA had an effect on TA deployment, preparation, and interactions, and on pupil engagement. However, this did not translate into an impact on pupil attainment.

  • Little girl sitting on the floor reading a book

    Evaluating the Accelerated Reader Scheme

    An evaluation of Renaissance Learning's AR scheme explored whether the programme has a positive effect on the reading comprehension of randomly assigned pupils, particularly those who are eligible for free school meals.

  • Yoga mat, mobile phone, dumbbells, bottle of water and measuring tape

    Evaluating the Wellbeing Premium Programme

    Small and medium enterprises (SMEs) often find it hard to invest in the health and wellbeing of their employees, or do not invest at all. Researchers evaluated a randomised controlled trial of a financial incentive programme to improve employee health and wellbeing in SMEs in the West Midlands.

  • Young school girls studying the heart using tablet computers

    Evaluating Digital Feedback in Primary Maths

    A partnership of primary schools in Lincolnshire developed an intervention that seeks to maximise the impact of teachers’ feedback on pupils’ outcome through the use of video. However, an efficacy trial and associated process evaluation of the intervention found that it does not improve pupil outcomes.

  • Young students conduct a planting experiment in science laboratory class

    Evaluating Primary Science Quality Mark

    A randomised controlled trial (RCT) evaluating the impact of PSQM sought to understand the impact of the intervention on pupils and teachers. The study also examined how the intervention is implemented.

  • Students raise their hands during class

    Exploring Why an Incentivised Pay Study Failed to Recruit Enough Teachers

    Researchers tried to conduct a randomised control trial to understand whether UK teachers could be motivated with incentivised pay and coaching, but they failed to recruit enough participants. To help future studies, they changed their research to explore why the recruitment effort failed.

  • Businesswoman suffering from neck pain at the office

    Evaluation of the Innovation Fund Health-led Trials

    Innovation Fund Health-led Trials test new ways to address sickness absence and the disability employment gap due to two main conditions: mental health and musculoskeletal disorders. RAND Europe, together with partners, evaluated the effectiveness of these innovative interventions.

  • Body worn cameras are being trialed by officers in Wolverhampton and Birmingham

    Body-Worn Cameras Associated with Increased Assaults Against Police

    Rates of assault against police officers are 15% higher when they wear cameras, possibly because they feel more confident about reporting assaults once they are captured on camera or because the officers did not keep their cameras on throughout their shift.