An introduction to the use of randomized control trials to evaluate development interventions

This guide provides a non-technical introduction to randomised controlled trials (RCTs).

It briefly covers what impact evaluation means before examining the problem of selection bias and how it can be dealt with through experimental and quasi-experimental designs.

Issues regarding designing and implementing an RCT are then discussed before moving on to some criticisms which are commonly made of this approach.

Contents

• Introduction
• What is impact evaluation?
• The problem of selection bias
• What to do about selection bias
• Issues in implementing an RCT
  • Preparing for an RCT
  • Designing the RCT (treatment arms, power calculations and all)
  • Reporting study design
  • Conducting the RCT
• Objections to RCTs
• Challenges for RCTs
• References
• Annex