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Randomised controlled trial

A randomised control trial (RCT) is a type of research experiment where participants are randomly assigned into two or more groups to test a specific intervention. An experimental group receives the intervention while a comparison or control group receives an alternative intervention, a placebo, or no intervention. RCTs are the gold standard method for testing the effectiveness of new health interventions, drugs, or treatments as, because they are so controlled, bias in the results is reduced.