Test, learn, adapt: developing public policy with randomised controlled trials

This paper from the UK Cabinet Office describes how random control trials can be used to assess the effectiveness of public policy interventions.


  • What is a randomised controlled trial?
  • The case for RCTs - debunking some myths
  • 1. We don’t necessarily know ‘what works’
  • 2. RCTs don’t have to cost a lot of money
  • 3. There are ethical advantages to using RCTs
  • 4. RCTs do not have to be complicated or difficult to run


  • Step1: Identify two or more policy interventions to compare
  • Step 2:Define the outcome that the policy is intended to influence
  • Step 3:Decide on the randomisation unit
  • Step 4:Determine how many units are required for robust results
  • Step 5: Assign each unit to one of the policy interventions using a robustly random method
  • Step 6: Introduce the policy interventions to the assigned groups


  • Step 7: Measure the results and determine the impact of the policy interventions


  • Step 8: Adapt your policy intervention to reflect your findings
  • Step 9: Return to step 1


Haynes, L., Service, O., Goldacre, B., & Torgerson, D. Cabinet Office, Behavioural Insights Team. (2012). Test, learn, adapt: Developing public policy with randomised controlled trials. Retrieved from website: http://www.cabinetoffice.gov.uk/sites/default/files/resources/TLA-190612...

Originally sourced from Monitoring and Evaluation NEWS