Measuring the success of blinding in placebo-controlled trials: Should we be so quick to dismiss it?

Abstract

'Blinding' involves concealing knowledge of which trial participants received the interventions from participants themselves and other trial personnel throughout the trial. Blinding reduces bias arising from the beliefs and expectations of these groups. It is agreed that where possible, blinding should be attempted, for example by ensuring that experimental and control treatments look the same. However, there is a debate about if we should measure whether blinding has been successful, this manuscript will discuss this controversy, including the benefits and risks of measuring blinding within the randomised controlled trial.

Keywords: Blinding; Masking; Measuring; Reporting guidelines; Trials.