Randomized Controlled Trials

What are randomized controlled trials?

Key Points

  • Randomized Controlled Trials (RCTs) are a type of study design commonly used in health research to explore the efficacy of interventions.
  • The goal of an RCT is to increase the validity of experimental results and strengthen the evidence for causal relationships.
  • RCTs use randomization, control groups, and blinding to control for variables and limit biases.

Helpful Links, Videos and Online Courses


  • Randomized Controlled Trial
    • An introduction to RCTs, including a step-by-step outline for how to design an RCT. Includes examples and tips in practice.


  • Randomized Controlled Trials (RCTs)
    • A video from UNICEF that highlights the importance of control groups in Randomized Controlled Trials, different RCT designs (including factorial, cluster, and multifactorial designs), and pitfalls to avoid in sampling procedures.
  • How do we know if an intervention works?
    • A 5-minute video describing how RCTs can be used to minimize bias and increase the validity of experimental findings, in terms of control groups and blinding.

Online Courses

  • Randomized Controlled Trials
    • A 30-minute video lecture on statistical interventions and methods commonly used in RCTs.
    • Note: the video refers to a textbook, but the video is helpful even without the textbook.

Relevant Publications

  • Stanley, K. (2007). Design of Randomized Controlled Trials. Circulation, 115(9), 1164–1169.
    • A comprehensive article from 2007 describing elements of RCT design, especially for clinical trials and health research