Abstract
In any clinical trial bias in determining treatment effects is one of the main concerns. Bias may be defined as systematic error, or “difference between the true value and that actually obtained due to all causes other than sampling variability” [1]. It can be caused by conscious factors, subconscious factors, or both. Bias can occur at a number of places in a clinical trial, from the initial design through data analysis, interpretation and reporting. One general solution to the problem of bias is to keep the participants and the investigators blinded, or masked, to the identity of the assigned intervention. One can also blind several other aspects of a trial including the assessment, classification and evaluation of the response variables. A large sample size does not reduce bias.
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Friedman, L.M., Furberg, C.D., DeMets, D.L., Reboussin, D.M., Granger, C.B. (2015). Blinding. In: Fundamentals of Clinical Trials. Springer, Cham. https://doi.org/10.1007/978-3-319-18539-2_7
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DOI: https://doi.org/10.1007/978-3-319-18539-2_7
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