Randomized controlled trial

A Randomized Controlled Trial (RCT) is a type of clinical trial where participants are randomly assigned to one of two or more groups to receive various interventions. These may include a test intervention, a control intervention, or no intervention at all. The process of random allocation enhances the credibility of the results by minimizing potential bias. The aim of an RCT is to determine the efficacy and safety of a new intervention by comparing its outcomes with those of existing treatments or placebo.<ref>Frieden, TR,

 Evidence for Health Decision Making - Beyond Randomized, Controlled Trials, 
 New England Journal of Medicine, 
 2017,
 
 
 DOI: 10.1056/NEJMra1614394,
 PMID: 28767355,</ref>

Design and Conduct of RCTs

RCTs are typically divided into four phases:

• Randomization: Participants are randomly assigned to various groups to avoid bias in the distribution of confounding variables. This is often accomplished using a random-number table or a computer-generated sequence.<ref>Julious, SA,

 Sample sizes for clinical trials with normal data, 
 Statistics in Medicine, 
 2004,
 
 
 DOI: 10.1002/sim.1783,
 PMID: 15211606,</ref>

• Intervention: Each group receives a different treatment or intervention. One group may receive the experimental treatment, while the control group may receive a standard treatment, a placebo, or no treatment at all.
• Follow-up: Participants are monitored over a period of time to evaluate the effects of the intervention. Data on outcomes, adverse events, and other relevant parameters are collected.
• Analysis: The collected data is analyzed to assess the efficacy and safety of the intervention. The results are compared between groups to determine any statistically significant differences.<ref>SC,

 Clinical Trials Handbook, 
  
 Wiley, 
 2009, 
  
  
 ISBN 9780470749484,</ref>

• RCTs may also incorporate features like blinding (where participants and/or researchers don't know which treatment a participant is receiving) and crossover (where participants receive multiple treatments in a random order) to further minimize bias and maximize the accuracy of the results.<ref>Porta, M,

 A dictionary of epidemiology, 
 International Journal of Epidemiology, 
 2008,
 
 
 DOI: 10.1093/ije/dyn085,
 PMID: 18381380,</ref>

Applications and Limitations

RCTs are considered the gold standard for determining the efficacy of new medical interventions due to their potential to limit systematic bias. They are widely used in developing clinical guidelines and policy decisions in healthcare.<ref>Bothwell, LE,

 Assessing the Gold Standard--Lessons from the History of RCTs, 
 New England Journal of Medicine, 
 2016,
 
 
 DOI: 10.1056/NEJMp1603753,
 PMID: 27276581,</ref>

However, RCTs are not without limitations. They can be expensive, time-consuming, and require a large number of participants. Ethical considerations can also limit their use, particularly when it's not considered appropriate or ethical to withhold a potentially beneficial treatment from a control group.<ref>London, AJ,

 Clinical Equipoise: Foundational Requirement or Fundamental Error?, 
 In Clinical Ethics in Pediatrics: A Case-Based Textbook, 
 2011,
 
 
 DOI: 10.1017/CBO9780511975817.007,
 PMID: 21842431,</ref>

See Also

• Clinical trial
• Evidence-based medicine
• Epidemiology
• Placebo-controlled study
• Blinding (clinical trials)

References

This article is a medical stub. You can help WikiMD by expanding it!
Most recent articles Ongoing trials	Wikipedia

Randomized controlled trial

• 
  Flowchart of Phases of Parallel Randomized Trial