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Changes In Beliefs Identify Unblinding In Randomized Controlled Trials: A Method To Meet Consort Guidelines, Judy R. Rees, Timothy J. Wade, Deborah A. Levy, John M. Colford, Joan F. Hilton

Journal Articles: Epidemiology

Double-blinded trials are often considered the gold standard for research, but significant bias may result from unblinding of participants and investigators. Although the CONSORT guidelines discuss the importance of reporting "evidence that blinding was successful", it is unclear what constitutes appropriate evidence. Among studies reporting methods to evaluate blinding effectiveness, many have compared groups with respect to the proportions correctly identifying their intervention at the end of the trial. Instead, we reasoned that participants' beliefs, and not their correctness, are more directly associated with potential bias, especially in relation to self-reported health outcomes. During the Water Evaluation Trial performed in …