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Randomized Controlled Trials 

Randomized Controlled Trials
Study Design and Statistics

Margaret A. Winker

and Stephen J. Lurie

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date: 21 January 2020

The randomized controlled trial (RCT) generally leads to the strongest inferences about the effect of medical treatments. Randomized controlled trials assess efficacy of the treatment intervention in controlled, standardized, and highly monitored settings, and usually among highly selected samples of patients. Thus, their results might not reflect the effects of the treatment in real-world settings, or in other groups of individuals who were not enrolled in the trial. Information from RCTs may thus be supplemented by results of observational studies (see , Observational Studies) as well as other types of studies. The methods of RCTs must be described in detail

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